University of Southern California Dissertations and Theses

Psychosocial adjustment among patients with metastatic colorectal cancer

(USC Thesis Other)

Psychosocial adjustment among patients with metastatic colorectal cancer

PDF

Download a page range

Download transcript

Copy asset link

Request this asset

Transcript (if available)

Content

PSYCHOSOCIAL ADJUSTMENT AMONG PATIENTS WITH METASTATIC
COLORECTAL CANCER

by
Stacy Ann Eisenberg

______________________________________________________________________________

A Dissertation Presented to the
FACULTY OF THE USC GRADUATE SCHOOL
UNIVERSITY OF SOUTHERN CALIFORNIA
In Partial Fulfillment of the
Requirements for the Degree
DOCTOR OF PHILOSOPHY
(PSYCHOLOGY)

August 2014

Copyright 2014 Stacy Ann Eisenberg

Table of Contents
List of Tables iii
List of Figures iv
Abstract v
Chapter 1: Introduction 1
Physical Symptoms 3
Cancer-related Ambiguity 6
Intrusive Thoughts 7
Social Activities 9
The Role of Intolerance of Uncertainty in the Association Between
Cancer-related Ambiguity and Emotional Distress
10
The Present Study 11
Chapter 2: Method 14
Participants 14
Procedures 15
Statistical Analyses 22
Chapter 3: Results 30
Part I. Descriptive Results 30
Part II. PLS Modeling 34
Chapter 4: Discussion 41
Limitations and Strengths 50
Conclusions and Future Directions 51
References

55
Appendix 1: Results for Full Hypothesized Model

93
Appendix 2: Questionnaire Packet 94

iii
List of Tables
Table 1: Descriptive statistics for demographic and medical variables

73
Table 2: Regression modeling predicting depression, anxiety, and emotional
dysfunction for covariate identification

75
Table 3: Factor loadings from exploratory factor analysis for Memorial Sloan
Kettering Cancer Center-Bowel Function Instrument

76
Table 4: Factor loadings from exploratory factor analysis for MUIS Ambiguity
subscale

77
Table 5: Factor loadings from exploratory factor analysis for non-somatic
CES-D

78
Table 6: Factor loadings from exploratory factor analysis for HADS-A

79
Table 7: Factor loadings from exploratory factor analysis for EORTC-QLQ-C30
emotional dysfunction subscale

80
Table 8: Factor loadings from exploratory factor analysis for IES-R Intrusive
Thoughts subscale
81
Table 9: Factor loadings from exploratory factor analysis for Social Activity Log
Social Activities subscale

82
Table 10: Confirmatory factor analyses

83
Table 11: Factor loadings from exploratory factor analysis for Intolerance of
Uncertainty Scale-Short Form

84
Table 12: Descriptive statistics for key variables

85
Table 13: Correlations of demographic, medical, and key study variables

86
Table 14: Comparison of hypothesized and trimmed PLS models

87
Table 15: Direct and indirect associations 88

iv
List of Figures
Figure 1: Full theoretical model including key variables

13
Figure 2: Full hypothesized structural model

89
Figure 3: Trimmed structural model

90
Figure 4: Interaction between intolerance of uncertainty and cancer-related
ambiguity in association with social activities

91
Figure 5: Interaction between social support and social activities in association
with emotional distress

92

v
Abstract
Objective: Patients with metastatic colorectal cancer (mCRC) may experience greater emotional
distress than patients with less advanced disease, but few studies have explored the aspects of the
mCRC experience that are related to poorer emotional functioning. The purpose of this study
was to test a model that identifies possible cancer-related and psychosocial correlates of
emotional distress in patients with mCRC. Methods: This cross-sectional, questionnaire-based
study included 102 patients participating in active treatment for mCRC. Partial least squares
(PLS) modeling analyses tested the key hypotheses, adjusting for months since diagnosis, cancer
surgery, and neuroticism. Results: In general, patients reported moderate emotional distress.
Greater physical symptoms and cancer-related ambiguity were directly associated with emotional
distress. Greater physical symptoms, cancer-related ambiguity, and intolerance of uncertainty
were associated with greater emotional distress indirectly, via their relations with greater
intrusive thoughts. Patients who experienced more physical symptoms also participated in fewer
social activities, but fewer social activities were only associated with distress in patients low in
social support. Conclusion: Patients with mCRC who report greater physical symptoms,
perceive their cancer experience as highly ambiguous, or view uncertainty as threatening may be
at elevated risk for emotional distress. Incomplete cognitive processing of the cancer experience,
marked by greater intrusive thoughts, may partially account for these relations.
1

Psychosocial Adjustment among Patients with Metastatic Colorectal Cancer
Despite the high prevalence rates of colorectal cancer in both men and women in the
United States (U.S. Cancer Statistics Working Group, 2010), few studies examine the
psychosocial adjustment of these patients. The studies that do exist often exclude entirely or
include only a few patients with metastatic disease even though there are vast differences in
symptoms, treatment, and prognosis between patients with and without metastases (Lynch,
Steginga, Hawkes, Pakenham, & Dunn, 2008; Medeiros, Oshima, & Forones, 2010; Tavoli et al.,
2007; Tsunoda et al., 2005). Metastatic disease is diagnosed in 20% of new colorectal cancer
patients, and 50% of patients with localized disease will eventually develop metastasis
(American Cancer Society, 2012). Living with colorectal cancer at any stage may be
challenging, but metastatic colorectal cancer (mCRC) may be particularly distressing given that
the cancer has spread, thus making treatment more complicated and cure less likely (Simon,
Thompson, Flashman, & Wardle, 2009). Surgical techniques and chemotherapy have made
major advancements in recent years in the treatment of cancer, but metastatic colorectal cancer
continues to be marked by low survivorship statistics. The five-year survival rate for patients
with metastatic colorectal cancer is 12%, compared to 91% for patients with localized disease
(American Cancer Society, 2012). Thus, palliation of physical and emotional symptoms and
improved quality of life remain important intervention goals for patients with mCRC (Arraras
Urdaniz et al., 2006; Kopetz et al., 2009).
Given the challenges described above, it may not be surprising that some patients with
mCRC experience emotional distress, but there is a paucity of literature examining the emotional
adjustment of patients with mCRC. The few studies that have examined psychological distress
in patients with colorectal cancer at any stage report a wide range of distress, with 6.7%-72.2%
of patients meeting the clinical cutoff for either depression or anxiety (Lynch, Steginga, Hawkes,
2
Pakenham, & Dunn, 2008; Medeiros, Oshima, & Forones, 2010; Tavoli et al., 2007; Tsunoda et
al., 2005). A possible explanation for this variability in the rates of distress is that these studies
often fail to differentiate distress levels among patients with different illness severities and
treatments. Patients with more advanced disease may be at higher risk for psychological distress
because their disease poses a greater threat to survival. They also face potentially
uncomfortable, draining, and embarrassing symptoms resulting from disease progression and
treatment (Medeiros et al., 2010; Simon et al., 2009). Few studies, however, include enough
patients with advanced diagnoses to examine the prevalence and correlates of emotional distress
in this patient population.
In a study that was sufficiently powered to compare distress among colorectal cancer
patients with different levels of disease severity (N = 128), 19% of the overall sample was highly
anxious and 14% was highly depressed (Simon et al., 2009). Patients with more advanced
disease had significantly higher anxiety and depression and poorer overall physical, emotional,
and functional wellbeing than patients with localized disease, adjusting for age, marital status,
and socioeconomic status. In a sample of 90 older adults receiving chemotherapy for metastatic
colorectal cancer, 14% of patients reported depressive symptoms above the clinical cutoff
(Aparicio et al., 2013). These studies suggest that a subset of patients with mCRC experience
clinically significant emotional distress.
Because cancer does not occur in a vacuum, it is important to examine together in one
model those cancer-related and general biopsychosocial constructs that might be associated with
emotional distress in order to better understand the complicated experience of patients with
mCRC. To this end, the following sections explore the literature regarding challenges facing
pa ti e nts wi th m e tasta ti c c olore c tal c a nc e r tha t m a y c ontribut e to patients’ e mot ional dis tre ss.
3
First, three prominent physical symptoms of mCRC (i.e., poor bowel function, fatigue, and pain)
and the extent to which patients perceive mCRC to be ambiguous will be examined in relation to
emotional distress. Then, dispositional and psychosocial issues that may help to explain why and
for whom physical symptoms or cancer-related ambiguity may be associated with distress will be
discussed.
Physical Symptoms
Patients with mCRC experience a wide variety of physical symptoms due to cancer
progression or treatments (e.g., surgery, radiation, chemotherapy) that can be managed but are
rarely entirely controlled (Carrato et al., 2013; Lesage & Portenoy, 1999). These symptoms
include, but are not limited to, problems in the gastrointestinal tract (e.g., bowel function
problems) as well as pain and fatigue (Kindler & Shulman, 2001; Maughan et al., 2002).
Bowel function. Patients with colorectal cancer commonly encounter problems with
bowel function including diarrhea, bowel urgency and frequency, fecal incontinence, and
constipation. Depending on cancer stage and treatment type, approximately 19-50% of patients
with colorectal cancer report bowel problems (Macvean, White, Pratt, Grogan, & Sanson-Fisher,
2007; Pan, Tsai, Chen, Tang, & Chang, 2011; Tol et al., 2009). Multiple aspects of mCRC
potentially contribute to poor bowel function. For example, possible symptoms of the disease
itself prior to treatment include bowel frequency, diarrhea, and constipation (Majumdar,
Fletcher, & Evans, 1999; Whynes & Neilson, 1997). Additionally, surgeries to remove the
primary colorectal cancer tumor, particularly low rectal anastomosis (i.e., a surgery where the
diseased portion of the rectum is removed and separated ends are reattached), often result in
problems with bowel function (Dehni et al., 1998). Medical advances have increased the
likelihood of sphincter-saving procedures and thus decreased the probability that surgeries will
result in a permanent stoma (Weiser et al., 2009). Although patients without a permanent stoma
4
tend to report better quality of life than those with a stoma (Sprangers, Taal, Aaronson, & te
Velde, 1995), they often still experience impairments of bowel functioning such as bowel
frequency and urgency (DeCosse & Cennerazzo, 1997; Pan et al., 2011). Problems with bowel
function have been shown to persist in approximately 37%-71% of rectal cancer patients five
years following surgery, with higher rates occurring for patients who had preoperative radiation
(Peeters et al., 2005). Diarrhea is a principal side effect of the chemotherapy agents most
commonly used among patients with advanced colorectal cancer and often becomes more severe
with prolonged chemotherapy (Glimelius, Hoffman, Graf, Påhlman, & Sjödén, 1994; Kindler &
Shulman, 2001; Maughan et al., 2002; Tol et al., 2009). Thus, poor bowel function appears to be
a common symptom of mCRC and its treatment.
Few studies have examined the impact of bowel function on the quality of life among
patients with mCRC despite the frequency and severity of this symptom. Difficulties with fecal
control at six months post diagnosis predicted poorer overall physical, emotional, social, and
functional wellbeing in patients with colorectal cancer at 24 months post diagnosis (Steginga,
Lynch, Hawkes, Dunn, & Aitken, 2009). In one qualitative study, patients reported that their
poor bowel function was embarrassing and that they experienced anxiety regarding finding an
available bathroom in time (Persson & Hellström, 2002). These studies suggest that patients
with mCRC who report poorer bowel function may be more likely to experience emotional
distress.
Fatigue. Fatigue is the most common symptom associated with cancer and its treatment
(Barnes & Bruera, 2002). Approximately 75% of patients receiving treatment for cancer
experience substantial fatigue (Cella, Davis, Breitbart, & Curt, 2001), and fatigue has been
identified as a major concern for patients with advanced colorectal cancer (Arraras Urdaniz et al.,
2006; Conroy, Bleiberg, & Glimelius, 2003). Cancer-related fatigue is the persistent, subjective
5
sense of tiredness related to cancer or cancer treatment (Mock et al., 2000). Cancer-related
fatigue, unlike that induced by exercise, is considered to be disproportionate or unconnected to
exertion and not mitigated by rest or sleep (Morrow, Andrews, Hickok, Roscoe, & Matteson,
2002). Fatigue is often one of the initial symptoms patients with cancer experience, and it
increases during the course of cancer treatment and disease progression. In patients with
metastatic cancer, fatigue can coexist with symptoms of pain, anorexia, insomnia, nausea, and
dyspnea, all of which can contribute to fatigue expression (Barnes & Bruera, 2002). Therefore,
fatigue may be a particularly distressing symptom for patients with mCRC.
The impact of fatigue on the emotional distress of patients with mCRC specifically has
rarely been examined, but fatigue has been shown to be associated with depression and anxiety
in mixed cancer samples (Munch et al., 2006; Smith, Gomm, & Dickens, 2003) and reduced
physical, social, emotional, and functional quality of life in patients with advanced cancer
(Barnes & Bruera, 2002; Gupta, Lis, & Grutsch, 2007). Additionally, fatigue was associated
with depression in patients across a range of stages of colorectal cancer (Schwenk, Böhm, &
Müller, 1998). Thus, given the frequency and severity of fatigue described above, it is suggested
that fatigue plays a prominent role in the emotional wellbeing of patients with mCRC.
Pain. Pain related to advanced colorectal cancer includes, but is not limited to pain in the
abdomen, bowel, rectum, or bones (Kindler & Shulman, 2001; Macvean et al., 2007).
Approximately 28-64% of patients with advanced colorectal cancer experience moderate to
severe pain at diagnosis and throughout the course of treatment (Macvean et al., 2007; Maughan
et al., 2002). Because the experience of pain is multidimensional and results from the complex
interaction between physiological, psychological, and social factors, pain management continues
to be an ongoing challenge for patients with metastatic cancer (Zaza & Baine, 2002; Ripamonti,
Bandieri, & Roila, 2011).
6
Across many types of cancer and stages of disease, cancer-related pain has demonstrated
a significant association with emotional distress including depression (Laird, Boyd, Colvin, &
Fallon, 2009) and anxiety (Brown, Kroenke, Theobald, Wu, & Tu, 2010; Reddick, Nanda,
Campbell, Ryman, & Gaston-Johansson, 2005; Tsunoda et al., 2005). For patients with
metastatic colorectal cancer, quality of life, including social and functional wellbeing, is
reportedly very much dependent on the control of pain (Dunn et al., 2003). Thus, pain appears to
be a physical symptom that is both frequently encountered and highly relevant to quality of life
in patients with mCRC.
Overall, patients with mCRC face a variety of physical symptoms that can range from
uncomfortable to debilitating. In addition to the visceral experience of these symptoms, another
cancer-related issue that may contribute to pa ti e nt s’ emotional distress is the extent to which they
perceive aspects of mCRC, such as the physical symptoms or illness trajectory, to be highly
unclear or unpredictable.
Cancer-related Ambiguity
Cancer-related ambiguity, the inability to assign definite value to objects or events and/or
to accurately predict outcomes, has been identified as a common experience among patients with
colorectal cancer (Galloway & Graydon, 1996; Northouse, Mood, Templin, Mellon, & George,
2000; Northouse, Schafer, Tipton, & Metivier, 1999; Shaha & Cox, 2003) and is possibly
exacerbated by the unique challenges of metastatic disease (Aranda et al., 2005). Patients with
mCRC may experience a high degree of cancer-related ambiguity because the cues about the
state of the cancer can be vague and indistinct. For example, similar somatic experiences (e.g.,
pain, diarrhea, or fatigue) have multiple potential interpretations, such as disease progression,
treatment side effects, or stress (Shaha & Cox, 2003; Shaha et al., 2008). Although the low five-
year survival rate suggests little uncertainty regarding long-term prognosis, it may be difficult for
7
patients to know whether their mCRC is improving, stable, or progressing at any given point in
time. It may also be difficult to predict how symptoms and side effects will present each day and
how these symptoms will int e rf e r e with one’ s dail y fun c ti oning .
Although no known studies have examined the association between cancer-related
ambiguity and emotional distress in patients with mCRC, this relation appears to exist in patients
with other types of cancer (Liao et al., 2008; Lien et al., 2009; Wallace, 2003; Wong &
Bramwell, 1992). For example, in older adult patients undergoing surgery for cancer, cancer-
related ambiguity was related to greater depressive symptoms, both before and after surgery
(Lien et al., 2009). Additionally, greater cancer-related ambiguity was associated with greater
anxiety in patients with prostate cancer (Wallace, 2003) and breast cancer (Liao et al., 2008; Lien
et al., 2009; Wong & Bramwell, 1992).
Physical symptoms and cancer-related ambiguity may be related to emotional distress
directly and/or indirectly via their associations with other psychosocial factors. Some physical
symptoms and treatment side effects may be present for the rest of mCRC pa ti e nts’ li ve s and most aspects of cancer-related ambiguity (e.g., ambig uit y re g a rdin g one ’s s pe c ific ill ne ss
trajectory) may also be difficult to eliminate. Therefore, it is important to examine potentially
modifiable cognitive and behavioral constructs that may partially explain the hypothesized
relations between these cancer-related issues and emotional distress.
Intrusive Thoughts
The experience of mCRC can be understood as a series of psychological and physical
stressors that begin with diagnosis and continue during treatment. Cognitive processing theory
suggests that discordance may occur between the cancer experience and pa ti e nts’ previous
beliefs about the self and the world (Creamer, Burgess, & Pattison, 1992). Subsequently,
adjustment requires e it he r c ha n g in g one ’s w or ldvi e w so that it is cong ru e nt with the experience
8
of having mCRC or c ha ng in g one ’s und e rsta ndin g of mCRC in order to incorporate it into
existing mental models. Both strategies require cognitive processing and integration of
information (Creamer, Burgess, & Pattison, 1992; Jim & Jacobsen, 2008). Intrusive thoughts,
the unwanted, involuntary thoughts or mental images related to a stressful event sometimes occur
during this process. Intrusive thoughts help to maintain information in active memory in order to
facilitate cognitive procesing and integration (Greenberg, 1995; Horowitz, Wilner, & Alvarez,
1979). Althoug h thi s pro c e ss m a y be b e ne fic i a l fo r the pa ti e nts’ lon g -term adjustment, intrusive
thoughts are often distressing. Specifically, greater intrusive thoughts have been shown to be
associated with anxiety, depression, and poorer overall quality of life in patients with breast
cancer (Anagnostopoulos, Slater, & Fitzsimmons, 2010; Lewis et al., 2001; Primo et al., 2000)
and prostate cancer (Lepore et al., 1996; Whitaker, Brewin, & Watson, 2008). Therefore,
intrusive thoughts may be associated with greater distress in patients with mCRC, and aspects of
the cancer experience may contribute to the maintenance of intrusive thoughts.
Because the mCRC experience is ongoing rather than a discrete event, cancer-related
issues (e.g., physical symptoms and ambiguity) may require ongoing cognitive processing, thus
maintaining intrusive thoughts. Frequent re-exposure to cues associated with the cancer (e.g.,
poor bowel function, pain, and fatigue) may hig hl ig ht t he dispar it y be tw e e n one ’s pr e vious c o re beliefs (e.g., I am safe and healthy) and the cancer experience, resulting in ongoing intrusive
thoughts (Devine, Parker, Fouladi, & Cohen, 2003). For example, in previous research intrusive
thoughts mediated the relation between cancer-related physical symptoms and emotional distress
in patients with breast cancer (Jim, Andrykowski, Munster, & Jacobsen, 2007). To the extent
that patients perceive their cancer experience as ambiguous, intrusive thoughts may also occur as
patients attempt to integrate unclear, unpredictable, or shifting information (Cordova,
Cunningham, Carlson, & Andrykowski, 2001; Lepore, Silver, Wortman, & Wayment, 1996).
9
Thus, greater physical symptoms and cancer-related ambiguity may be associated with greater
emotional distress in part because of their relation with greater intrusive thoughts.
Social Activities
Participation in fewer social activities may also partially account for the associations of
physical symptoms and cancer-related ambiguity with emotional distress. The physical
symptoms experienced by patients with mCRC may be particularly limiting with regards to
social activities (e.g., attending a party, eating a meal at a restaurant with others) because some
symptoms may be perceived as embarrassing (e.g., bowel incontinence, flatulence) and others
might be debilitating (e.g., pain, fatigue). Although not specifically tested in patients with
mCRC, greater physical symptoms have been shown to be associated with poorer social
functioning in patients with cancer (Steginga et al., 2009; Strang, 1992). For example, in a
sample of patients with non-metastatic colorectal cancer, fatigue and difficulties with fecal
control were significantly associated with poorer social wellbeing 24 months after cancer
diagnosis (Steginga et al., 2009). Higher levels of cancer-related pain have also been related to
lower participation in social activities (Strang, 1992).
Perceiving a high degree of cancer-related ambiguity may also be related to less social
participation in cancer patients. In one study with patients receiving radiation therapy for
uterine, cervical, head and neck, or lung cancer, cancer-related ambiguity was associated with
participation in fewer social activities (Christman & Cain, 2004). Patients might have been
avoiding situations in which questions or comments from family or friends might have
exacerbated ambiguity-related discomfort. Furthermore, if patients have difficulty predicting
when certain physical symptoms will occur, they possibly will avoid participating in social
situations to prevent embarrassment or frequent last-minute cancellations (Christman & Cain,
2004; Persson & Hellström, 2002).
10
The activity restriction model hypothesizes that emotional distress occurs as a result of
life stresses (e.g., cancer and its treatment) that interfere with social and recreational activities
because the opportunities for positive reinforcement and social connectedness are limited
(Mausbach et al., 2011; Williamson & Shaffer, 2000). Previous psychosocial oncology research
has reported a n a sso c iation betwe e n low e r pa rticipa ti on in s oc ial a c ti vit ies a nd c a n c e r p a ti e nts’
increased emotional distress (Syrjala, Stover, Yi, Artherholt, & Abrams, 2010). Overall social
functioning has also been associated with greater emotional wellbeing in patients with mCRC
(Efficace et al., 2008). Thus, previous work suggests that cancer-related physical symptoms and
ambiguity may impede participation in social activities, and restriction in social activities may be
related to greater emotional distress in patients with cancer. The direct and indirect associations
among these constructs, however, have yet to be tested in a single model or within the specific
context of mCRC.
The Role of Intolerance of Uncertainty in the Association Between Cancer-related
Ambiguity and Emotional Distress
Uncertainty in Illness Theory suggests that some patients may be better able to adapt to
cancer-related ambiguity than others (Mishel, 1997, 1999). Intolerance of uncertainty is one
characteristic that may help to distinguish which patients are more likely to experience emotional
distress if they perceive mCRC to be highly ambiguous. Intolerance of uncertainty can be
defined as a cognitive bias that affects how a person perceives, interprets, and responds to
uncertain situations on a cognitive, emotional, and behavioral level (Dugas, Schwartz, & Francis,
2004). Specifically, patients who are highly intolerant of uncertainty regard uncertainty as
stressful, frustrating, and threatening (Buhr & Dugas, 2002). Intolerance of uncertainty has been
associated with greater depressive symptoms in patients with breast cancer (Costa-Requena,
Rodríguez, Fernández, Palomera, & Gil, 2011) and higher perceptions of stress, poorer
11
emotional well-being, and depressive symptoms in patients with lung cancer (Kurita, Garon,
Stanton, & Meyerowitz, 2013). The latter study did not find a significant interaction between
cancer related ambiguity and intolerance of uncertainty in their association with emotional
distress, though with 49 participants the study may have been underpowered to detect this effect.
Although both cancer-related ambiguity and intolerance of uncertainty may be independently
associated with greater emotional distress, intolerance of uncertainty may also exacerbate the
relation between cancer-related ambiguity and distress (Dugas, Schwartz, & Francis, 2004;
Mishel, 1997, 1999). In a sample of 153 healthy undergraduates, there was a significant
interaction between intolerance of uncertainty and situational ambiguity in their association with
health-related anxiety, such that ambiguity was associated with greater anxiety in all participants
but the association was stronger for participants who were highly intolerant of uncertainty
(Rosen & Knäuper, 2009). Therefore, patients who perceive their mCRC experience to be
highly ambiguous and who also view ambiguous situations as threatening (i.e., intolerant of
uncertainty) may be at particularly high risk for experiencing emotional distress.
The Present Study
Previous research suggests that emotional distress may be higher among patients with
metastatic cancer than those with localized disease (Simon et al., 2009), but few studies have
explored the interplay between cancer-related and psychosocial issues that are related to greater
emotional distress. The purpose of this study was to test a model, grounded in psychological
theory, that represents the psychosocial adjustment to mCRC and is derived from four primary
goals (see Figure 1). The first goal was to explore emotional distress among patients receiving
treatment for mCRC and to examine its relation with cancer-related physical symptoms and
ambiguity. Specifically, it was hypothesized that greater physical symptoms would be associated
with greater cancer-related ambiguity, and both greater physical symptoms and ambiguity would
12
be directly associated with greater emotional distress. The second goal was to examine potential
mediators of physical symptoms and cancer-related ambiguity as they relate to emotional distress
in order to identify potential targets for psychological intervention. It was hypothesized that
physical symptoms and cancer-related ambiguity would be indirectly related to emotional
distress via their relations to intrusive thoughts and lower participation in social activities.
The third goal was to investigate intolerance of uncertainty as a potential moderator of
the association between cancer-related ambiguity and emotional distress in order to better
identify which patients found ambiguity to be particularly distressing. Because it was
hypothesized that intrusive thoughts and lack of social activities would partially account for the
association between ambiguity and emotional distress, the current study explored the role of
intolerance of uncertainty in the associations between cancer-related ambiguity and emotional
distress, intrusive thoughts, and social activities. First, it was hypothesized that intolerance of
uncertainty would moderate the relation between cancer-related ambiguity and emotional
distress, such that cancer-related ambiguity would be more strongly associated with emotional
distress for patients who were higher in intolerance of uncertainty than those who were lower.
Second, it was hypothesized that intolerance of uncertainty would moderate the association
between cancer-related ambiguity and intrusive thoughts, such that cancer-related ambiguity
would be more strongly associated with intrusive thoughts for patients who were higher in
intolerance of uncertainty than those who were lower. Third, it was hypothesized that
intolerance of uncertainty would moderate the association between cancer-related ambiguity and
social activities, such that ambiguity would be more strongly associated with fewer social
activities for patients who were higher in intolerance of uncertainty that those who were lower.
The last goal was to examine the exploratory question of how these hypothesized
relations might differ whether or not neuroticism, the general tendency to experience negative
13
emotion, was included in the statistical model. Neuroticism was included to help to distinguish
between (1) the overall tendency to experience distress and actually experiencing distress in the
particular context of mCRC and (2) the tendency to be rigid and negative in general and
intolerance of uncertainty specifically. Study goals were explored while holding constant the
effects of relevant medical and demographic variables.

Figure 1. Full theoretical model including key variables

14
Method
Participants
Adult patients who were receiving active treatment for a diagnosis of metastatic
colorectal cancer (i.e., stage IV) were recruited from the USC Norris Comprehensive Cancer
Center Gastrointestinal Cancers Program for participation in the study. Eligible participants
must also have exhibited the physical and mental ability to complete questionnaires, as
determined by their physician during their regularly scheduled medical appointment, and have
been able to read and write in English. Patients with history of malignancy other than metastatic
colorectal cancer or treated squamous/basal cell carcinoma of the skin were excluded from the
study.
Descriptive statistics for demographic and medical variables are provided in Table 1. A
total of 102 patients with metastatic colorectal cancer was recruited over a 22-month period from
the USC Norris Comprehensive Cancer Center Gastrointestinal Cancers Program. Mean age for
the sample was approximately 55 years, and it was two-thirds Caucasian. Approximately half of
the participants were female and the majority of them were married or partnered.
On average, patients participated approximately two years after their diagnosis with
metastatic disease, but time since diagnosis ranged from less than one month to 14 years.
Treatment modality options for patients included surgery, chemotherapy, radiation therapy, and
targeted drug therapy (e.g., Avastin, Erbitux). The majority of participants (59%) had received
two types of treatment (usually surgery and chemotherapy), 20% one type of treatment, 20%
three, and 1% four treatment modalities. Most patients did not currently require a stoma
(colostomy or ileostomy). P h y sicia n r a ti ng s of p a r ti c ipants’ Re sponse E va l ua ti on Crit e ria in
Solid Tumors (RECIST; Therasse et al., 2000; Eisenhauer et al., 2009) indicate that participants
15
were approximately evenly divided between responding to treatment, having stable disease, and
having progressive disease at the time of assessment.
Procedures
The treating physician or nurse practitioner invited all eligible patients to participate in
the study during their regularly scheduled oncology clinic visit. Patients were informed that their
participation was strictly voluntary and should they wish not to participate, their treatment at the
cancer center would not be affected. If a patient declined to participate, the patient was asked to
complete a brief demographic form assessing age, gender, marital status, education, and ethnicity
for the purpose of recruitment statistics. When it was determined that a patient was interested in
participating in the study, the physician or nurse practitioner invited the study investigators to
conduct the informed consent procedures . One o f the stud y investi g a tors e nter e d the p a ti e nt’s
private treatment room and briefly explained the study. Written consent was obtained for the
self-report questionnaires and the medical information form that was completed by the medical
provider.
Following informed consent, participants completed a contact information form that
included their name, address, telephone number, and email address and the name and telephone
number of their primary caregiver. Participants indicated on this form whether it was acceptable
for the study investigators to leave a detailed message on their answering machines. They also
completed the brief demographic information form that assessed age, gender, marital status,
education, and ethnicity. They were then given the option of completing the questionnaires
privately in the clinic and returning them to study investigators (40%), or completing them at
home and returning them in a postage-paid envelope that was provided to them at the time that
they received the questionnaires (60%). Participants were asked to complete the questionnaires
independently and reported that it took them 30-60 minutes on average to complete the packet.
16
Study investigators contacted participants via telephone with a reminder if they did not return
their questionnaire packet within 14 days of receipt. If after three phone attempts the
questionnaire packet was not returned, the circumstance was not e d in t he p a ti e nt’s st ud y f il e a nd
the patient was not contacted any further for the study. Treating providers completed a brief
medical information form for each participant. The USC Health Sciences Internal Review Board
and the USC Norris Comprehensive Cancer Center Clinical Investigations Committee approved
this study.
Study investigators were introduced to a total of 137 patients with metastatic colorectal
cancer who were eligible for recruitment, but two of these patients died prior to completing the
assessment (within 2 weeks of initial contact). A total of eight participants declined to
participate either to the nurse or to the study investigators prior to signing consent because they
were not interested in participating (N = 6), did not have time (N = 1), or were not feeling well
enough to participate (N = 1). After consent was obtained, 23 participants did not return
questionnaires. Fourteen of these patients were reached by telephone and gave the following
reasons for withdrawing from the study: length of the questionnaires (N = 3), negative feelings
triggered by the questionnaire (N = 2), no longer being interested (N = 4), and lack of time (N =
5). The remaining nine did not respond when contacted. Therefore, the study had a 76%
recruitment rate. The average ages of the 102 participants (M = 55.07, SD = 11.24) and the 31
eligible patients who chose not to participate (M = 56.19, SD = 11.62), were not significantly
different [t(126) = 0.45, p = 0.65]. Chi-square tests of independence showed that participation
was not significantly related to gender [ Χ
2
(1, N = 131) = 0.00, p = 0.992], marital status [ Χ
2
(1,
N = 131) = 2.31, p = 0.128], college education [ Χ
2
(1, N = 131) = 0.04, p = 0.837], or Caucasian
ethnicity [ Χ
2
(1, N = 131) = 0.47, p = 0.49]. Study investigators did not have access to medical
data for patients who declined participation.
17
Instruments.
Demographic and medical information. Demographic information included age,
ethnicity, sex, income, education, and marital status. Basic medical information was collected on
a separate form that was completed by each patient ’s treating nurse practitioner or physician.
This form assessed the p a ti e nt’s pr im a r y c a nc e r si te ( c olon or r e c tum ), da t e of the mC R C diagnosis, past and current cancer treatment type(s) (i.e., chemotherapy, radiation, surgery,
and/or targeted therapy), stoma status, and Response Evaluation Criteria in Solid Tumors
(RECIST; Therasse et al., 2000; Eisenhauer et al., 2009) score. The RECIST score measures
tum or r e sponse to tre a tm e nt and r a n ge s fr om z e ro (“ C ompl e te r e sponse ” ) to thre e ( “ P rogr e ssi ve disea se ” ).
Neuroticism. Neuroticism was measured in order to test whether the key variables were
associated with emotional distress after adjusting for a general tendency to experience negative
emotions. The 12-item neuroticism subscale of the Short-Scale Eysenck Personality
Questionnaire-Revised is a reliable and empirically-validated questionnaire (EPQR-N; Eysenck,
Eysenck & Barrett, 1985) that was used to assess neuroticism, or the tendency to experience
negative emotions. The measure asks participants whether or not they experience various
characteristics of neuroticism (e.g. mood-fluctuations, nervousness), rated one (“ Y e s” ) or zero
(“ No” ). The total scale score is a sum of item totals, with higher scores indicating greater
ne ur oti c ism . Cronba c h’ s a lpha in thi s sample was 0.79.
Key predictor variables.
Physical symptoms. Physical symptoms formed a latent variable with the observed
variables pain, fatigue, and bowel function as its formative indicators.
Pain and fatigue. Pain was assessed with the two items that form the pain subscale of the
European Organization for Research and Treatment of Cancer Quality of Life Questionnaire
18
(EORTC QLQ-C30; Aaronson et al., 1993). As suggested in The EORTC QLQ-C30 Scoring
Manual (3rd Edition; Fayers, Aaronson, et al. 2001), the items were averaged. Fatigue was
assessed using the three items that form the EORTC QLQ-C30 fatigue subscale. A mean of
these items was used in the analyses.
The EORTC QLQ-C30 assesses functional status and symptomatology relevant to
patients with cancer. Symptoms experienced during the past month are rated on a four-point
sc a le f rom on e ( “ Not a t a ll ” ) to f our ( “ Ve r y much ” ). H ig h e r sc o re s on e a c h it e m i ndica te mor e cancer-related pain or fatigue. This scale has demonstrated good internal consistency reliability
and validity in colorectal cancer populations (Neuman et al., 2007; Whistance et al., 2009).
Many published clinical trials use the EORTC QLQ-C30 to measure physical symptoms in
colorectal cancer patients (Palmer, Martling, Lagergren, Cedermark, & Holm, 2008; Whistance
et al., 2009), so its inclusion in the current study will allow for a clear comparison to published
results. C ronba c h’ s a lpha w a s 0.87 a nd 0.86 for pain and fatigue, respectively in this study.
Bowel function. Bowel function was measured with the 15 items of the Memorial Sloan
Kettering Cancer Center-Bowel Function Instrument (Temple et al., 2005). This scale measures
bowel function experienced in the past month in patients with colorectal cancer. Bowel function
is rated on a five- point sc a le r a n g in g f rom one ( “ A lwa y s ” ) to f ive (“ N e ve r ” ) . A sum score was
used in analyses and higher scores indicate better bowel function. This measure has been shown
to reliably and validly measure bowel function in patients with colorectal cancer and is
commonly used in conjunction with the EORTC-QLQ (Murata, Brown, Raval, & Phang, 2008;
Temple et al., 2005) . Cr onba c h’ s alph a wa s 0.87 in this study.
Cancer-related ambiguity. The 13 items composing the Ambiguity subscale of the Mishel
Uncertainty in Illness Scale-Adult Form (MUIS; Mishel, 1981) assessed cancer-related
ambiguity. The MUIS measures ambiguity occurring in situations where the patient is unable to
19
assign definite value to objects or events and/or is unable to accurately predict outcomes. This
scale was designed to measure ambiguity in hospitalized or acutely ill adults, and has shown
good reliability and validity in patients with cancer (Mishel, 1997). Ambiguity experienced in
the past month is measured on a five-point scale ran g in g f rom one ( “ S trong l y disa g r e e ” ) to f ive
(“ S trong l y a g re e ” ). Hig h e r sc or e s re fle c t g r e a te r cancer-related ambiguity, and a sum of the
items was used in the analysis. C ronba c h ’s a lpha wa s 0.87 i n thi s sample.
Outcome variable.
Emotional distress. Emotional distress was analyzed as a latent variable predicted by
three reflective indicators: anxiety, depression, and emotional dysfunction.
Anxiety. The Hospital Anxiety and Depression Scale-Anxiety subscale (HADS-A;
Zigmond & Snaith, 1983) consists of seven items rated on a four-point scale from zero to three;
each item has different response options. This measure identifies anxiety symptoms experienced
among medically ill patients in the past month. Item scores are summed to create a composite
score; higher scores indicate more anxiety. Specifically designed for use with medically ill
patients, the HADS-A excludes symptoms of anxiety that may be associated with physical illness
(e.g. dizziness, heart palpitations, and sweating). The scale has demonstrated good internal
reliability in patients with cancer as well as concurrent validity with other established measures
of state and trait anxiety (Bjelland, Dahl, Haug, & Neckelmann, 2002) . Cr onba c h’ s alph a wa s
0.78 in this sample.
Depression. Depressive symptomatology was measured using the Center for
Epidemiologic Studies Depression Scale (CES-D; Radloff, 1977) whose reliability, validity and
clinical utility have been well established (Weissman, Sholomskas, Pottenger, Prusoff, & Locke,
1977). The scale contains 20 items representing clinical manifestations of depression,
experienced in the past month, that are rated on a four- point sca le f rom z e ro ( “ R a re l y o r non e of
20
the tim e ” ) to thre e (“ Mos t or a ll of the ti me” ) . Items are summed to create a total score with
higher scores indicating greater depressive symptoms. The five items assessing somatic
symptoms (i.e., bothered b y thi n g s that don’t usual l y bother me , appetite, effort, sleep, get going;
Radloff, 1977) were removed from the variable used in the PLS modeling analyses due to their
c onfou ndin g with s y mpt oms o f me tasta ti c c olore c tal c a n c e r a nd it s tre a tm e nt. C ronba c h’ s a lpha
for the 15 items was 0.87 in this sample.
Emotional dysfunction. Emotional dysfunction was assessed using the four-item
Emotional Dysfunction subscale of the EORTC QLQ-C30 (Aaronson et al., 1993). Symptoms of
emotional distress experienced during the past month are rated on a four-point scale from one
(“ Not a t all” ) to f our ( “ V e r y much” ). Sc or e s on e a c h it e m were averaged, with higher scores
indicating greater emotional dysfunction. This scale has demonstrated good internal consistency
reliability and validity in a colorectal cancer population (Neuman et al., 2007; Whistance et al.,
2009). C ronba c h’ s a lpha f or thi s sample was 0.81.
Potential mediators.
Intrusive thoughts. The Impact of Events Scale-Revised (IES-R; Horowitz et al., 1979;
Weiss, 2007) is an e mpi ric a ll y v a li da ted me a sur e that a ssesse s an indivi dua l’s re a c ti ons t o a stressful event, in this case, colorectal cancer. Patients rate the degree to which intrusive
thoughts (e . g ., unw a nted thoug hts, i mage s, or dr e a ms) “ with re spe c t t o y our c ol or e c tal c a nc e r” have bothered them during the past month. Items are rated on a five-point scale, ranging from
z e ro ( “ Not a t all” ) to f our ( “ Ex tre mel y ” ). An average of the eight items comprising the Intrusive
Thoughts subscale was used in the analyses, and higher scores reflect greater intrusive thoughts.
Internal reliability for the Intrusive Thoughts subscale has been shown to be adequate (Weiss,
2007). This measure has been validated in patients with metastatic cancer (Badr, Carmack,
21
Kashy, Cristofanilli, & Revenson, 2010) and colorectal cancer (Norum, 1997). C ronba c h’ s a lpha
was 0.87 in this sample.
Social activities. Engagement in social activities was measured with the seven-item
Social Activity subscale of the Social Activity Log (Logsdon & Teri, 1997; Syrjala et al., 2010).
Items assess the frequency with which participants have engaged in activities outside the home
and whe r e other s a re p re s e nt over the pa st m onth. R e sponse options r a n g e f rom z e ro ( “ Not a t
a ll ” ) to f our ( “ Da il y ” ). T his m e a sure has been shown to reliably and validly measure the social
activity of patients with cancer (Syrjala et al., 2010). A mean score was used in the analyses, and
higher scores reflect greater participation in social activities. C ronba c h’ s al pha wa s 0.71 i n thi s
sample.
Potential moderator.
Intolerance of uncertainty. The 12-item Intolerance of Uncertainty Scale-Short Form
(IUS-SF; Carleton, Norton & Asmundson, 2007) assesses the extent to which participants
believe that uncertainty is unacceptable and leads to inaction and frustration. Items are rated on
a five- point sca l e , r a n g in g f rom one ( “ Not c ha ra c t e risti c of me a t all” ) to f i ve ( “ Entire l y characteristic of me ” ). Intole ra nc e o f uncertainty was analyzed as a latent variable predicted by
three reflective indicators, the scores for each of the three subscales of the IUS-SF. The
subscales measure the extent to which uncertainty interferes with action (Inaction subscale),
uncertainty is upsetting (Upsetting subscale), and uncertainty regarding the future is
unacceptable (Future subscale). The Inaction, Upsetting, and Future subscales included 5, 3, and
4 items, respectively. Items comprising each subscale were summed, and higher scores indicated
greater intolerance of uncertainty. The scale has been shown to be reliable and empirically valid
in community and cancer populations (Buhr & Dugas, 2002; Costa-Requena, Rodríguez,
22
Fernández, Palomera, & Gil, 2011). C ronba c h’ s a lphas in this study were 0.83, 0.81, and 0.71 for
the Inaction, Upsetting, and Future subscales, respectively.
Additional variables assessed for descriptive purposes.
Social support. Social support was measured by the Medical Outcomes Study Social
Support Survey (Sherbourne & Stewart, 1991). This 19-item functional support scale was
developed to assess the levels of perceived availability of social support among patients with
chronic illness. Responses are based on a five-point scale that ranges from one (“ Non e of the ti me” ) to five (“ All of the ti me” ), and the mean score was used in the analyses. This scale has
demonstrated adequate reliability and validity in chronically ill populations (Sherbourne &
Stewart, 1991). C ronba c h’ s alpha in t his sample was 0.95.
Social interference. P e r c e ived inter f e re n c e of on e ’s ill ne ss and tr e a tm e nt o n soc ial
activities was assessed using the two-item Social Functioning subscale of the EORTC QLQ-C30
(Aaronson et al., 1993). Symptoms of social interference experienced during the past month are
rated on a four- point sca l e f rom one ( “ Not a t all” ) to four ( “ V e r y much ” ). S c or e s on e a c h it e m
were averaged, with higher scores indicating greater interference with social activities. This
scale has demonstrated good internal consistency reliability and validity in a colorectal cancer
population (Neuman et al., 2007; Whistance et al., 2009). C ronba c h’ s a lpha f or thi s sample was
0.89.
Statistical Analyses
Preliminary analyses.
Descriptive statistics and covariate identification. Descriptive statistics, including
mea ns, st a nda rd d e viations , a nd ra n g e s we r e c a l c ulate d to desc ribe th e pa r ti c ipants’
demographic, medical, and psychosocial characteristics.
Regression modeling was used to identify potential covariates of the relation between the
23
predictor and outcome variables. In separate equations, the three components of emotional
distress (depression, anxiety, and emotional dysfunction) were regressed on a block of potential
covariates, and t-tests assessed the significance of their parameter estimates at the 0.10 level of
significance. These results are presented in Table 2. Potential covariates included gender,
marital status (married or partnered/not partnered), income, Caucasian ethnicity, age, months
since mCRC diagnosis, radiation therapy, cancer-related surgery, tumor response (RECIST) and
neuroticism. All significant correlates of depression, anxiety, or emotional dysfunction (i.e.,
neuroticism, radiation therapy, cancer-related surgery, and months since diagnosis) were
included in the PLS modeling analyses.
Missing data. Five participants were missing data from one scale, the MSKCC-BFI.
Two participants indicat e d that the y didn’t t hink t he mea sur e of bo w e l func t ioni ng a ppli e d to
them due to their stoma, and for three participants the reason is unknown. As soon as packets
with missing data were returned, participants were contacted and asked to complete the missing
data. Unfortunately, these five participants did not return completed information after these
requests. No other scales were missing data from more than one participant. Thus, the level of
missing data was well below the general rule of thumb that a dataset should not have any column
with more than 10 percent of its values missing (Hair et al., 1987; 2009). Warp-PLS statistical
software replaced any missing values with the column averages for each variable (Kock, 2013).
Factor analyses. In order to assist with designing the PLS measurement model, factor
analyses tested the factor structure of key study variables (i.e., bowel function, cancer-related
ambiguity, depression, anxiety, emotional dysfunction, intrusive thoughts, social activities, and
intolerance of uncertainty). Exploratory factor analyses were conducted with a Maximum
Likelihood extraction and Promax rotation to allow for correlation between factors. Factors were
e x tra c ted ba se d on K a ise r’ s cr it e ri a ( e i ge nva lue > 1;; Ka iser , 1960) a nd examination of the Scree
24
plot (Cattell, 1966). The Kaiser-Meyer-Olkin measure of sampling adequacy (KMO; Kaiser,
1970; Kaiser, 1974) was examined to establish whether the data were suitable for factor analysis
(rule of thumb: KMO > 0.50; Williams, Brown, & Onsman, 2012). Items with loadings greater
than 0.30 were considered satisfactory and included in the variable sum or mean (Osborne &
Costello, 2005). Because fatigue and pain were composed of three and two items, respectively,
exploratory factor analyses were not conducted for these variables.
Bowel function. The Kaiser-Meyer Olkin measure of sampling adequacy indicated that
the data were suitable for the exploratory factor analysis of the 15 Memorial Sloan Kettering
Cancer Center-Bowel Function Instrument (KMO = 0.82). The exploratory factor analysis
yielded a one-factor solution, with all item loadings > 0.40 (see Table 3). Therefore, a sum of
the 15 items formed the bowel function variable that was a reflective indicator of physical
symptoms in the PLS modeling analyses.
Cancer-related ambiguity. The Kaiser-Meyer Olkin measure of sampling adequacy
indicated that the data were suitable for the exploratory factor analysis of the 13 Ambiguity
subscale items of the MUIS (KMO = 0.84). The exploratory factor analysis yielded a one-factor
solution, with all item loadings > 0.40 (see Table 4). Therefore, a sum of the 13 items formed
the cancer-related ambiguity variable in the PLS modeling analyses.
Depression. The Kaiser-Meyer Olkin measure of sampling adequacy indicated that the
data were suitable for the exploratory factor analysis of the 15-item CES-D that excluded
somatic items (KMO = 0.81). The exploratory factor analysis yielded a one-factor solution, with
all item loadings > 0.30 (see Table 5). Therefore, a sum of the 15 items formed the depression
variable that was one of the reflective indicators for emotional distress in the PLS modeling
analyses.
25
Anxiety. The Kaiser-Meyer Olkin measure of sampling adequacy indicated that the data
were suitable for the exploratory factor analysis of the seven-item HADS-A (KMO = 0.78). The
exploratory factor analysis yielded a one-factor solution, with all item loadings > 0.35 (see Table
6). Therefore, a sum of the seven items formed the anxiety variable that was one of the reflective
indicators for emotional distress in the PLS modeling analyses.
Emotional dysfunction. The Kaiser-Meyer Olkin measure of sampling adequacy indicated
that the data were suitable for the exploratory factor analysis of the four-item emotional
dysfunction subscale of the EORTC-QLQ-C30 (KMO = 0.78). The exploratory factor analysis
yielded a one-factor solution, with all item loadings > 0.60 (see Table 7). Therefore, a mean of
the four items formed the emotional dysfunction variable that was one of the reflective indicators
for emotional distress in the PLS modeling analyses.
Intrusive thoughts. An exploratory factor analysis of the eight items forming the IES-R
Intrusive Thoughts subscale was conducted, and the Kaiser-Meyer Olkin measure of sampling
adequacy suggested that the sample was factorable (KMO = 0.85). The analysis yielded a one-
factor solution, with all item loadings > 0.40 (see Table 8). The mean of the eight items formed
the intrusive thoughts variable for the PLS modeling analyses.
Social activities. The Kaiser-Meyer Olkin measure of sampling adequacy indicated that
the data were suitable for the exploratory factor analysis of the seven Social Activity subscale
items of the Social Activity Log (KMO = 0.70). The exploratory factor analysis yielded a one-
factor solution, and item loadings were all > 0.40 (see Table 9). The mean of the seven items
was used for the social activities variable in the PLS modeling analyses.
Intolerance of uncertainty. Because the authors who designed the IUS-SF reported a two-
factor structure for the measure, a confirmatory factor analysis compared the fit to the data of
this two-factor model with the fit of a one-factor model. Model fit assessments included the chi-
26
square, root mean squared error of approximation (RMSEA), comparative fit index (CFI), and
non-normed fit index (NNFI). The chi-square test measures the extent to which the model
deviates from a perfect fit to the empirical data. The RMSEA assesses misfit of a model to a
sample. The CFI measures increments in model fit compared to the null model. The NNFI is an
incremental fit index that assesses significant incremental changes from the null model to the
model being tested. The values that were indicative of better fit included chi-square values
closer to zero, RMSEA closer to zero, CFI closer to one, and NNFI closer to one (Kline, 2005).
Model specifications included setting the error variance of the factor to one and allowing all
other factor loadings and the error variances of the measured variables to vary. Results of the
confirmatory analysis are presented in Table 10. The two-factor model proposed by Carleton,
Norton & Asmundson (2007) fit the data significantly better than the one-factor model, Δ χ
2
=
23.87, (df = 1, N = 102, p < 0.001). Because the two-factor model still showed substantial misfit
to the data, however, an exploratory factor analysis was used to examine the factor structure of
the 12 items. The Kaiser-Meyer Olkin measure of sampling adequacy suggested that the sample
was factorable (KMO = 0.86). The analysis yielded a three-factor solution and results are shown
in Table 11. Five items loaded on the first factor and were related to uncertainty interfering with
action (i.e., Inaction subscale). Three items loaded on the second factor, and these items were
related to uncertainty being upsetting (i.e., Upsetting subscale). Four items loaded on the third
factor, and they appeared to measure the idea that uncertainty regarding the future is
unacceptable (i.e., Future subscale). The three factors were significantly correlated (rs = 0.40-
0.59, ps < 0.01) and no items had loadings less than 0.40 on their respective factors or greater
than 0.30 on another factor. Therefore, intolerance of uncertainty was included in the PLS
modeling analysis as a latent variable predicted by the three IUS-SF subscale scores.
Partial least squares modeling. Partial least squares (PLS; Wold, 1975) modeling using
27
WarpPLS statistical software was used to test the study hypotheses. PLS is recommended
instead of covariance-based structural equation modeling methods when sample sizes are small
relative to the number of exogenous variables in the model (Haenlein & Kaplan, 2004). PLS
also works without distributional assumptions and with nominal, ordinal, and interval scaled
variables (Fornell & Bookstein, 1982).
PLS focuses on maximizing the variance of the endogenous variables explained by the
exogenous variables. A PLS model consists of a measurement component (i.e., relationships
between latent variables and indicator variables) and a structural component (i.e., relationships
between the latent variables; Chin & Newsted, 1999). The full, hypothesized PLS structural
model is presented in Figure 2.
Measurement component. Latent variables represent the constructs of physical
symptoms, intolerance of uncertainty, and emotional distress. Latent variables contain only the
shared variance of the observed variables, thus reducing error and improving reliability of the
latent variable. Indicators for the emotional distress latent variable included the scores for the
HADS-A, CES-D, and EORTC QLQ-C30 emotional dysfunction subscale. Indicators for the
intolerance of uncertainty latent variable included the three subscale scores for the IUS-SF (i.e.,
Inaction, Upsetting, and Future). Indicators for the physical symptoms latent variable were the
scores for the Bowel Functioning Index and EORTC QLQ-C30 fatigue and pain subscales. The
remaining constructs (i.e., cancer-related ambiguity, social activities, intrusive thoughts,
neuroticism, surgery, radiation, and months since diagnosis) had one observed indicator with a
loading of one. All indicators were reflective except for physical symptoms, which had
formative indicators. A reflective latent variable is one in which all the indicators are expected
to be highly correlated with the latent variable score. A formative latent variable is one in which
the indicators are expected to measure certain attributes of the latent variable, but the indicators
28
are not required to be highly correlated with one another or the latent variable score (Vinzi, Chin,
& Henseler, 2009). Because bowel dysfunction, pain, and fatigue are all physical symptoms of
the cancer or its treatment that do not necessarily occur together and were not all highly
correlated (bowel function and fatigue: -0.18, bowel function and pain: -0.24, pain and fatigue
0.39), it was decided that a formative variable was most appropriate.
The indicator weights and factor loadings that link the indicators to their respective latent
variables were estimated through an iterative process. Each latent variable is calculated as a
linear combination of its indicators, where the weights are multiple regression coefficients
linking the indicators to the latent variable. Construct reliability and validity were tested using
the c ompos it e r e li a bil it y (CR), C ronba c h’ s alph a , indicator loadings, and the average variance
extracted (AVE) for the reflective latent variables . A CR a nd Cronba c h’ s alpha greater than 0.60
and an AVE greater than 0.50 are indicative of sufficient reliability and validity (Bagozzi & Yi,
1988; Vinzi, Chin, & Henseler, 2009). For reflective variables with multiple indicators (i.e.,
emotional distress and intolerance of uncertainty), indicator loadings greater than 0.40 should be
retained in the final measurement model (Hulland, 1999). Indicator weights, p-values and
variance inflation factors were examined for the formative indicators of physical symptoms
(Vinzi, Chin, Henseler, & Wang, 2010). P-values less than 0.05 for indicator weights and
variance inflation factors less than 2.5 indicate that the formative latent variable measurement
items are valid and therefore should be retained in the measurement model (Vinzi, Chin,
Henseler, & Wang, 2010).
Structural component. After the final measurement model was established, case values
for each latent variable were used in a set of regression equations to determine the parameters for
the structural relations, and the model was restricted to linear associations (Haenlein & Kaplan,
2004). The bootstrapping resampling procedure (500 samples) then produced t-statistics,
29
standard errors, and p-values for these parameters. As recommended by Falk & Miller (1992),
path coefficients and R
2
s were considered to determine how well the model fit the data using
several rules of thumb: (1) R
2
s for endogenous variables should be > 0.10 and (2) a predictor
variable should account for at least 1.5% of the variance in the predicted variable. According to
the rule of parsimony and the inductive a pproa c h of model trim mi ng , a “ tri mm e d” model wa s
then run by eliminating paths that accounted for less than 1.5% of the variance of a predicted
component (Falk & Miller, 1992). The variance in emotional distress explained by the two
models was then compared and the specific hypotheses below were then tested as part of the
“ trimm e d” P L S model.
Analysis for key hypotheses using PLS modeling. To test whether greater physical
symptoms and cancer-related ambiguity were associated with greater emotional distress, the
statistical significance of the coefficients for the paths associating physical symptoms and
cancer-related ambiguity with emotional distress was calculated. Significant, positive regression
coefficients would support this hypothesis.
To test the meditational hypotheses, the significance of the coefficients for paths
signifying indirect associations between physical symptoms and cancer-related ambiguity with
emotional distress via intrusive thoughts and social activities was tested. Significant mediation
was indicated if the coefficient for the path signifying the indirect effect differed significantly
from zero (Preacher & Hayes, 2004). Next, nested models were compared to test whether the
explained variance for emotional distress decreased significantly when the path between the
mediator and emotional distress was removed from the model.
For the moderation hypotheses, all possible products from the two sets of mean-centered
indicators for cancer-related ambiguity and intolerance of uncertainty were used to develop
product indicators. These product indicators were then used to estimate the latent variable
30
representing the interaction between cancer-related ambiguity and intolerance of uncertainty
(Chin, Marcolin, & Newsted, 2003). Significant moderation was indicated if the path coefficient
associating the latent interaction variable with emotional distress, intrusive thoughts, or social
activities differed significantly from zero (Baron & Kenny, 1986; Hopwood, 2007).
Exploratory analysis. For the exploratory analysis, neuroticism was removed from the
model and the hypothesized relations between key variables were tested again. The variance in
emotional distress explained by the predictors in this new model (R
2
) was compared with the R
2

for emotional distress for the trimmed model that included neuroticism.
Results
Part I. Descriptive Results
Descriptive statistics for the key study variables are presented in Table 12. Results from
correlation analyses inclu ding P e a rson c or r e lations f or c onti nuous va ria bl e s and S pe a rma n ’s r ho
correlations for dichotomous variables are presented in Table 13.
Pain. On a v e ra ge , pa rtic ipants re porte d e x pe rie n c ing “ a li tt le bit” of pain (i.e., subscale
score of two) in the past month. Thirty-eight percent of patients, however, reported experiencing
“ quit e a bit ” to “ve r y much” pa in overall (i.e., subscale score > three). The most commonly
reported locations of the pain were in the abdomen (24 %) and the buttocks/anal area/rectum (14
%). Twenty-three percent of patients reported that their pain interfered with their daily activities.
These results are comparable to means reported from age-matched normative data from 499
European men and women (z = 0.77; Hinz, Singer & Brahler, 2014) and 91 cancer patients (z =
0.05; Hjermstad, Fayers, Bjordal & Kaasa, 1998 ) pr ovided b y the sc a l e ’s a uthors. None of the
demographic or medical variables tested were significantly correlated with pain.
Fatigue. On a ve ra g e , p a rticipa nts re porte d “ quit e a bit ” of f a ti g ue . Fatigue in this
sample was high compared to the age-matched normative data from 499 European men and
31
women (z = 1.84; Hinz, Singer & Brahler, 2014) and comparable to fatigue reported in the
normative sample of 91 cancer patients (z = 0.31; Hjermstad, Fayers, Bjordal & Kaasa, 1998).
Specifically, 55 % of p a rt icipa nts re porte d fe e li n g “ quit e a bit ” to “ve r y much” fatigue (i.e.,
subscale score > three). An additional 35% of patients indicated they felt “ a li tt le bit” of fatigue
(i.e., subscale score of two). None of the demographic or medical variables tested were
significantly correlated with fatigue.
Bowel function. On a ve ra g e , pa ti e nts e x pe rie nc e d pro blems wit h bowe l f unc ti on “ ra rely
to sometimes, ” and the average score was comparable to means from another sample of 198
patients with colorectal cancer (z = 0.58; Temple et al., 2005). The most common complaints
occurring at least some of the time (i.e., BFI item score < three) were loose stool (51%), not
feeling like one had totally emptied his or her bowels after a bowel movement (45%), having
another bowel movement within 15 minutes of the last one (40%), and having diarrhea (34%).
Additionally, 38% of participants said they felt embarrassed about problems with bowel
function. It was less common, however, for patients to soil their undergarments with stool
(10%), be unable to wait 15 minutes to get to the toilet for a bowel movement (17%), be unable
to control the passage of gas (17%), or need to take medicine to decrease the number of bowel
movements (19%). Of the demographic and medical covariates, college education and higher
income were significantly correlated with better bowel function.
Cancer-related ambiguity. Scores on the MUIS in this sample were high compared to a
sample of 40 patients receiving treatment for localized colorectal cancer (z = 1.64; Galloway &
Graydon, 1996) and comparable to means reported in a sample of 49 patients with advanced lung
cancer (z = -0.55; Kurita et al., 2013). Specifically, 65% of patients said that they agreed or
strongly agreed (MUIS item score > four) that “ th e c ourse o f m y il lness ke e ps ch a n g in g ;; I ha v e g ood a nd b a d da y s ” a nd 45% that “ be c a use o f th e tre a tm e nt, wha t I c a n do and cannot do keeps
32
c ha n g in g .” F or t y pe r c e nt “ a g re e d” o r “ stron g l y a gr e e d” th a t “it i s not c lea r wha t i s g oin g to
ha ppe n to m e ” or “ it is unclear how bad my pain will be. ” Older age, lower income, and poorer
tumor response to treatment (RECIST) were correlated with greater cancer-related ambiguity.
Emotional distress.
Anxiety. Applying the guideline of the HADS-A (Callahan & Wolinsky, 1994), 75% of
the patients reported little or no anxiety symptoms (< eight), 16% showed borderline anxiety
(scores ranging from eight to 10), and nine percent reported severe anxiety (>10) warranting
clinical attention. Of all the demographic and medical variables tested, only female gender was
significantly associated with greater anxiety.
Depression. Scores on the complete CES-D (including psychological and somatic
symptoms) were examined for descriptive purposes in order to compare this sample with
previously established norms. Forty-three percent of all participants scored at or above the
established cut-off score of 16 (Radloff, 1977), which is used to identify individuals “at risk for
clinical depression. ” When the somatic items were removed and sum scores were prorated so
that the clinical cut-off score could be applied, 41% of patients scored at or above the clinical
cut-off. Female gender and lower income were the demographic variables correlated with
greater depressive symptoms, and no medical variables were correlated with depression.
Emotional dysfunction. On average, participants in this sample reported “ a li tt le” emotional dysfunction, with 23% e x pe rie nc ing p ro blems “ quit e a bit ” to “ve r y much ” of the time. Mean levels of emotional dysfunction reported in this sample were similar to means
reported in both the European general population normative sample (N = 499) and the cancer
patient normative sample (N = 91) for the EORTC QLQ-C30 (zs = 0.77 and 0.61, respectively;
Hinz, Singer, Brahler, 2014; Hjermstad, Fayers, Bjordal & Kaasa, 1998). The most commonly
reported difficulties with emotional functioning e x pe rie nc e d “ quit e a bit ” to “ ve r y much ” of the
33
time were worrying (32%) and feeling irritable (25%). Female gender and history of surgery
were correlated with greater emotional dysfunction.
Intrusive thoughts. Twenty-seven percent of participants reported intrusive thoughts that
exceeded the clinical cutoff for PTSD re-experiencing symptomatology (IES-R intrusive
thoughts subscale = 1.5, Creamer, Bell & Failla, 2003). In other words, 27% of participants
reported that intrusive thoughts had b e e n “ m ode ra tel y ” to “ e x tre mel y ” ( i.e., I ES -R Intrusive
Thoughts score > 2) bothersome in the past month. For example, 53% of participants reported
that any reminder brought back feelings about their colorectal cancer. Levels of intrusive
thoughts were comparable to those reported in a sample of 558 patients with breast cancer
(Dupont, Bower, Stanton & Ganz, 2014). Female gender was positively correlated with intrusive
thoughts, but none of the other demographic or medical variables tested was correlated with
intrusive thoughts.
Social activities. Patients generally participated in social activities outside the home one
to three times per month (i.e., SAL item score of one). The most common activities in which the
patients participated at least once in the past month included attending a party or social gathering
(77%), visiting the homes of friends (75%), eating a meal at a restaurant with others (57%), and
shopping with others (55%). Higher income and not having a stoma were associated with greater
participation in social activities.
Intolerance of uncertainty. On average, participants reported similar levels of
intolerance of uncertainty to a normative community sample of 571 Canadians (z = -0.60;
Carleton et al., 2012) and lower than a normative sample of 63 patients diagnosed with
Generalized Anxiety Disorder (z = -1.54; Carleton et al., 2012). Twenty-two percent of
participants indicated that intolerance of uncertainty was at least “ somew h a t cha ra c ter ist ic” of
them (IUS-SF item score > three). Of the three subscales, intolerance of uncertainty about the
34
future had the highest endorsement, with 31% of participants reporting it was a t l e a st “some wha t
c ha ra c ter ist ic” o f the m. Married or partnered relationship status was correlated with lower levels
of intolerance of uncertainty.
Neuroticism. Twenty percent of patients reported no symptoms of neuroticism, and
approximately 80% of patients scored in the lower half of the scale. Levels of neuroticism for
the sample were in the average range compared to means from normative data of 902 adults from
a community sample (z = -0.64, Eysenck, Eysenck & Barrett, 1985). Women reported greater
neuroticism than men.
Social support. Participants reported high levels of social support, with 73% reporting
that support has be e n a v a il a ble if ne e de d “ most of the tim e ” to “a ll of the ti me” ( i.e., a v e r a g e score > four). Of the demographic and medical variables, married patients reported higher social
support.
Social interference. Fifty-one percent of participants reported that their mCRC or its
treatment has interfered with their social activities at least “ quit e a bit ” of the time (subscale
score > three). Social interference was not correlated with any of the demographic or medical
variables.
Part II. PLS Modeling
Measurement model.
Formative indicators. The weights for the formative indicators of the physical symptoms
latent variable were all significant at the p < 0.001 level, equaling 0.51, 0.49 and -0.38 for
fatigue, pain, and bowel function, respectively. These results suggest that all three variables
were valid indicators of physical symptoms. Additionally, the variance inflation factors for
fatigue, pain, and bowel function were 1.187, 1.217, and 1.068, respectively. These VIF values
are below the recommended acceptable threshold (VIF < 2.50) and suggest that the indicators of
35
physical symptoms are not redundant. Lastly, the square root of the AVE for physical symptoms
was higher than any of the correlations involving this variable, suggesting good discriminant
validity. Therefore, pain, fatigue, and bowel function were retained as indicators of physical
symptoms in the final measurement model.
Reflective indicators. The reliability and validity of the latent variables with multiple
reflective indicators (i.e., emotional distress and intolerance of uncertainty) were evaluated in the
measurement model. The loadings for emotional distress were 0.89, 0.90, and 0.90 for
depression, anxiety, and emotional dysfunction, respectively. They were all significant at the p <
0.001 level. The composite reliability and AVE for emotional distress were 0.92 and 0.80 and
were therefore greater than the required threshold of 0.50 for composite reliability and 0.60 for
AVE. Taken together, these results suggest sufficient construct reliability and validity. The
square root of the AVE for emotional distress was also higher than any of the correlations
involving this variable, indicating good discriminant validity. Therefore, depression, anxiety,
and emotional dysfunction were retained as indicators of emotional distress in the final
measurement model.
The loadings for the intolerance of uncertainty latent variable were 0.87, 0.92, and 0.78
for the Inaction, Upsetting, and Future subscales, respectively. They were all significant at the p
< 0.001 level. The composite reliability and AVE for intolerance of uncertainty were 0.89 and
0.72 and were therefore greater than the required thresholds. Taken together, these results
suggest sufficient construct reliability and validity. The square root of the AVE for intolerance
of uncertainty was also higher than any of the correlations involving this variable, indicating
good discriminant validity. Therefore, the three subscales were retained as indicators of
intolerance of uncertainty in the final measurement model.

36
Structural model.
The complete hypothesized model including covariates is presented in Figure 2 (see
Appendix 1 for results from this model). Using the inductive approach to model trimming (Falk
& Miller, 1992), paths that accounted for less than 1.5% of the variance of an endogenous
variable were removed from the originally hypothesized model. Because radiation did not
account for more than 1.5% of the variance in any of the endogenous variables, the variable was
removed from the final model. Fourteen of the original 26 paths from the original model were
retained in the “ trimm e d ” model (see Figure 3). The R
2
values for emotional distress in the
hypothesized and trimmed models were compared, and these results are presented in Table 14.
The hypothesized model did not account for significantly greater variance in emotional distress
than the trimmed model. The trimmed model is considered more parsimonious and was
therefore used for hypothesis testing.
Direct prediction of emotional distress. The first goal of this study was to examine the
association between physical symptoms and cancer-related ambiguity and to test their relations
to emotional distress. Greater physical symptoms were associated with greater cancer-related
ambiguity ( β = 0.53, p < 0.001). Additionally, greater physical symptoms ( β = 0.22, p = 0.005)
were directly associated with greater emotional distress, but cancer-related ambiguity ( β = 0.10,
p = 0.13) was not directly associated with distress. Of the tested covariates, greater neuroticism
(β = 0. 26, p < 0.001), fewer months since mCRC diagnosis (β = -0.11, p = 0.02), and history of
surgery (β = 0.1 2, p = 0.03) were significantly associated with greater emotional distress. Thus,
the first hypothesis was partially confirmed because greater physical symptoms were associated
with greater cancer-related ambiguity and greater emotional distress, but ambiguity was not
directly associated with emotional distress in the context of the entire model.

37
Indirect prediction of emotional distress.
The second goal was to explore whether intrusive thoughts with re g a rd to one ’s cancer or
participation in social activities partially accounted for the hypothesized associations of physical
symptoms and cancer-related ambiguity with emotional distress. Greater cancer-related
ambiguity was significantly associated with greater intrusive thoughts ( β = 0.21, p = 0.004).
Additionally, greater intrusive thoughts were associated with greater emotional distress ( β =
0.44, p < 0.001). The indirect association between cancer-related ambiguity and emotional
distress through intrusive thoughts was also significant (indirect effect = 0.09, p = 0.01). When
the path between intrusive thoughts and emotional distress was removed from the model,
ambiguity was significantly associated with emotional distress (β = 0. 19, p = 0.008). When this
path is removed, however, the R
2
for emotional distress drops from 70% to 60% ( Δ R
2
= .10, p =
0.04), indicating that the model including the path between intrusive thoughts and emotional
distress explains significantly more variance in emotional distress than the model excluding it. A
third model was tested, in which ambiguity and intrusive thoughts had direct paths to distress,
but the indirect path from ambiguity to distress via intrusive thoughts was removed. In this
model, intrusive thoughts (β = 0. 44, p < 0.01), but not ambiguity (β = 0. 09, p = 0.11), was
significantly associated with emotional distress, and the R
2
for emotional distress was unchanged
(R
2
=0.70). These results show that although cancer-related ambiguity is not directly associated
with emotional distress in the context of the entire model, it is indirectly associated with greater
emotional distress via its relation to greater intrusive thoughts.
Physical symptoms were not significantly associated with intrusive thoughts, and they did
not explain a large enough portion of its variance (i.e., 0.18%) for the path to be retained in the
final model. Therefore, physical symptoms were not indirectly associated with emotional
distress via intrusive thoughts. There was, however, a significant indirect association between
38
physical symptoms and emotional distress through ambiguity and then intrusive thoughts (β =
0.05, p = 0.02). In other words, greater physical symptoms were associated with greater
ambiguity ( β = 0.53, p < 0.001), which was associated with greater intrusive thoughts ( β = 0.21,
p = 0.004), which was associated with greater emotional distress ( β = 0.44, p < 0.001). Thus, in
addition to their direct association with distress, physical symptoms were indirectly associated
with greater distress through their relations to cancer-related ambiguity and intrusive thoughts.
Two additional indirect associations with emotional distress via intrusive thoughts were
evident in the final model. First, intolerance of uncertainty was indirectly associated with
emotional distress through its association with intrusive thoughts (indirect effect = 0.14, p =
0.003). Greater intolerance of uncertainty was significantly associated with greater intrusive
thoughts ( β = 0.33, p < 0.001), which was associated with gr e a te r e mot iona l di stre ss (β = 0.44, p
< 0.001). Neuroticism was also indirectly associated with emotional distress through its
association with intrusive thoughts (indirect effect = 0.14, p = 0.006). Specifically, greater
neuroticism was associated with greater intrusive thoughts (β = 0.33, p < 0.001), which was
a ssocia ted w it h g re a ter e mot ional dis tre ss (β = 0.44, p < 0.001). The combined effects of cancer-
related ambiguity, physical symptoms, intolerance of uncertainty, intrusive thoughts,
neuroticism, months since mCRC diagnosis, and surgery accounted for 70% of the variance in
emotional distress, F (6, 95) = 31.33, p < 0.001.
The second construct that was hypothesized to link physical symptoms and cancer-related
ambiguity to emotional distress was less participation in social activities. Greater physical
symptoms ( β = -0.15, p = 0.03) but not cancer-related ambiguity (β = -0.11, p = 0.08) were
significantly associated with less participation in social activities. Because social activities were
not related to emotional distress, there was not a significant indirect association between physical
symptoms and emotional distress through social activities. Contrary to the hypothesis, social
39
activities did not mediate the association between either cancer-related ambiguity or physical
symptoms and emotional distress.
Testing intolerance of uncertainty as a moderator.
The third goal of this study was to investigate intolerance of uncertainty as a moderator
of the relations between cancer-related ambiguity and emotional distress, intrusive thoughts, and
social activities. Results showed a significant interaction between intolerance of uncertainty and
cancer- r e late d a mbi g uit y on soc ial a c ti vit ies ( β = 0 .2 0, p = 0.02). Together, ambiguity, physical
symptoms, intolerance of uncertainty, and the interaction between ambiguity and intolerance of
uncertainty accounted for 11% of the variance in social activities, F (4, 97) = 2.37, p = 0.04.
The specific nature of the interaction between cancer-related ambiguity and intolerance
of uncertainty on social activities was investigated by testing the association between ambiguity
and social activities in two subgroups of patients, those whose levels of intolerance of
uncertainty were one standard deviation above and one standard deviation below the mean
(Aiken & West, 1991). Contrary to the hypothesis, in those patients whose intolerance of
uncertainty was one standard deviation above the mean, cancer-related ambiguity was not
significantly associated with social activities (β = 0. 14, p = 0.08). In those patients whose
intolerance of uncertainty was one standard deviation below the mean, greater cancer-related
ambiguity was associated with less participation in social activities (β = -0.62, p < 0.001; see
Figure 4). Therefore, cancer-related ambiguity was associated with less participation in social
activities only in those patients who were not intolerant of uncertainty.
The paths between the interaction term and both intrusive thoughts and emotional distress
were not retained in the final model (explained variance in the original model was 0.35% and
0.08%, respectively). Thus, there were not significant interactions between cancer-related
40
uncertainty and intolerance of uncertainty in their associations with either intrusive thoughts or
emotional distress.
Exploratory analysis.
For the exploratory analysis, neuroticism was excluded from the trimmed model. The
only changes in relations that occurred were that greater intolerance of uncertainty ( β = 0. 18, p =
0.01) and history of surgery ( β = 0. 13, p = 0.04) became significantly associated with greater
emotional distress. The model excluding neuroticism explained 66% of the variance in
emotional distress ( Δ R
2
= .10, p = 0.16), which was not significantly less than the trimmed
model that includes neuroticism.
Post-hoc analyses.
Because the results did not support the hypothesized relation between less participation in
social activities and greater emotional distress, interference with social activities and social
support were examined as potential moderators of this hypothesized association. Significant
moderation was indicated if the path coefficient associating the latent interaction variable with
emotional distress differed significantly from zero.
There was not a significant interaction between perceived social interference (β = -0.04, p
= 0.27) and social activities in their associations with emotional distress, but social interference
was directly associated with greater emotional distress (β = 0. 14, p = 0.03). There was a
significant interaction between social support and social activities in their association with
emotional distress (β = 0. 13, p = 0.04). The specific nature of the interaction between social
activities and social support on emotional distress was investigated by testing the association
between social activities and emotional distress in two subgroups of patients, those whose levels
of social support were one standard deviation above the mean and one standard deviation below
the mean (Aiken & West, 1991). In patients who were high in social support, participation in
41
social activities was not significantly associated with distress (β = 0. 04, p = 0.35). In patients
who reported low levels of social support, however, less participation in social activities was
significantly associated with greater emotional distress (β = -0.24, p = 0.01; see Figure 5).
Lastly, the association between intolerance of uncertainty and cancer-related ambiguity in
relation to emotional distress was explored. Specifically, it was tested whether intolerance of
uncertainty was indirectly associated with emotional distress through cancer-related ambiguity
and then intrusive thoughts. The significance of the coefficient for the path signifying an indirect
association between intolerance of uncertainty with emotional distress via cancer-related
ambiguity and then intrusive thoughts was tested (Preacher & Hayes, 2004).
Results showed a significant indirect association between intolerance of uncertainty and
emotional distress through cancer-related ambiguity and then intrusive thoughts (indirect effect =
0.02, p = 0.04). In other words, greater intolerance of uncertainty was associated with greater
ambiguity ( β = 0.24, p = 0.002), which was associated with greater intrusive thoughts ( β = 0.21,
p = 0.004), which was associated with greater emotional distress ( β = 0.44, p < 0.001). Thus,
patients with greater intolerance of uncertainty were more likely to perceive their cancer
experience as ambiguous, which in turn was related to greater emotional distress via intrusive
thoughts.
Discussion
Although rates of survival remain well below those for localized colorectal cancer,
treatment advances have extended the lives of patients with mCRC (American Cancer Society,
2012). However, the psycho-oncology literature examining the psychosocial adjustment of these
patients is surprisingly limited. The purpose of this study was to describe the emotional
experience of patients with mCRC and to identify cancer-related (i.e., physical symptoms,
ambiguity), psychosocial (intrusive thoughts, social activities), and dispositional (intolerance of
42
uncertainty, neuroticism) factors that are associated with emotional distress in these patients.
Additionally, this study explored whether the psychosocial and dispositional variables mediated
or moderated the association between these cancer-related issues and emotional distress in order
to identify potentially modifiable factors that could be targets for intervention and to help better
recognize patients in greatest need of psychological treatment.
This sample of patients with mCRC reported moderate rates of emotional distress, which
were comparable to published rates in patients undergoing treatment for mCRC (Nasta et al.,
2003; Rich et al., 2005). Because a majority of patients reported little to no emotional distress, it
should not be assumed that distress is an unavoidable aspect of the mCRC experience. However,
this study did identify a subgroup of patients who were more likely to report distress, and levels
of depression in this sample were higher than those previously reported in patients with localized
colorectal cancer (e.g., Lynch, Steginga, Hawkes, Pakenham, & Dunn, 2008; Medeiros, Oshima,
& Forones, 2010; Tsunoda et al., 2005). Emotional distress was not measured prior to cancer
diagnosis, so it cannot be concluded whether the cancer itself directly contributed to distress.
Physical symptoms, radiation therapy, surgery, and fewer months since diagnosis were
associated with greater distress in the multiple regression analysis, so it is unlikely that the
reported emotional distress was completely the result of pre-cancer psychopathology.
The experience of greater physical symptoms was one key aspect of mCRC hypothesized
to be associated with greater emotional distress. The types and frequency of physical symptoms
reported by this sample were in concert with the existing literature on symptoms in mCRC
(Barnes & Bruera, 2002; Arraras Urdaniz et al., 2006; Conroy et al., 2003; Macvean et al., 2007;
Maughan et al., 2002). Similar to previous research, the majority of patients reported feeling
fatigued. Fatigue can result from the disease itself or its treatment and commonly occurs in the
context of chemotherapy (Innominato et al., 2012). Those patients who experienced fatigue also
43
reported more pain, and these symptoms commonly co-occur in patients with advanced cancer
(Thornton, Andersen, Blakely, 2010; Theobald, 2004). Approximately one third of the patients
reported substantial pain, particularly in the abdomen, buttocks, anal area, and rectum. On
average, pa ti e nts r e porte d that pr oblems wit h bowe l func ti oning o c c ur re d “ ra re l y ” to
“ someti mes.” Approximately 40% of the patients experienced at least some infrequent problems
with bowel frequency and urgency. These symptoms include diarrhea, the principal side effect
of the chemotherapy agents most commonly used among patients with mCRC (Glimelius et al.,
1994; Kindler & Shulman, 2001; Maughan et al., 2002; Tol et al., 2009). Although physicians
attempt to manage these symptoms through medical interventions, for most patients mCRC is a
progressive illness and physical changes related to the disease and its treatment may not be
eliminated entirely. As predicted, the experience of greater physical symptoms (i.e., poor bowel
function, fatigue, and pain) was related to greater emotional distress, which is consistent with a
previous study in patients with colorectal cancer (Steginga et al., 2009).
One potential explanation for the observed association between physical symptoms and
emotional distress is that the co-occurrence of pain, fatigue, and depression may result from a
common etiological mechanism. Neuroendocrine-immune models of cancer symptoms
(Cleeland et al., 2003; Dantzer et al., 2008; Millet et al., 2008; Thornton Andersen, Blakely,
2010) suggest that these symptoms cluster together in part due to an inflammatory reaction
involving the activation of the sympathetic nervous system and hypothalamic-pituitary-adrenal
(HPA) axis. Treatment with radiation and chemotherapy may also elicit increases in
proinflammatory cytokines, further contributing to these symptoms (Bower, 2007; Miller,
Ancoli-Israel, Bower, Capuron & Irwin, 2008). Indeed, fatigue and pain had slightly stronger
correlations with depression than anxiety. This possibility could be tested in future studies that
include neuroendocrine assessments. It is also possible that greater physical symptoms serve as
44
a proxy for disease severity. In other words, patients with progressive illness may have
experienced both greater physical symptoms and emotional distress. This explanation is less
likely because one measure of disease severity (i.e., tumor response) was not significantly
associated with distress.
Perceived ambiguity was the second cancer-related characteristic hypothesized to be
associated with greater emotional distress. The most common complaints regarding cancer-
related ambiguity were related to the changing course of the illness and its impact on
functioning, the fluctuating severity of physical symptoms, and an unclear and unpredictable
future. It is particularly interesting that the participants reported perceiving high rates of cancer-
related ambiguity, given that they were highly educated and likely had access to available
information. Therefore, the cancer-related ambiguity that they reported would likely not be
eliminated with informational intervention. As hypothesized, greater cancer-related ambiguity
was associated with greater distress, but only when intrusive thoughts were excluded from the
model.
A goal of this study was to examine psychosocial factors that may help to explain why
patients who have greater physical symptoms or cancer-related ambiguity might experience
greater emotional distress. Specifically, greater intrusive thoughts were hypothesized to link
greater physical symptoms and cancer-related ambiguity to emotional distress. As was
predicted, patients who perceived their cancer to be more ambiguous also tended to experience
more unwanted, involuntary thoughts or images related to their cancer, which in turn were
associated with greater overall emotional distress.
Although physical symptoms were not directly associated with intrusive thoughts, they
were indirectly associated via cancer-related ambiguity. Patients who experienced more physical
symptoms viewed their cancer experience as more ambiguous, possibly because they were
45
unsure of the meaning of nonspecific symptoms, when symptoms would flare, and how they
would feel on a particular day. Perceived ambiguity, in turn, was associated with emotional
distress indirectly via intrusive thoughts. Therefore, not only was the experience of the physical
symptoms distressing. Physical symptoms were also linked to distress because they may lead
patients to perceive their cancer experience as more ambiguous, which may interfere with the
processing of cancer-related information and contribute to distress.
Cognitive processing theory suggests that adjusting to a trauma often requires the
processing and integration of trauma-related information, and intrusive thoughts signal
incomplete processing (Creamer et al., 1992). Perhaps perceiving cancer-related information as
unclear, fluctuating, and unpredictable requires ongoing processing of this shifting information
and therefore maintains intrusive thoughts related to the cancer experience (Cordova et al., 2001;
Lepore et al., 1996). Alt houg h thi s proc e ss m a y b e be ne fi c ial fo r the p a ti e n ts’ long -term
adjustment, intrusive thoughts are often distressing (Jim & Jacobsen, 2008), and an association
between intrusive thoughts and emotional distress was found in this sample of patients with
mCRC. Unfortunately, the cross-sectional design of this study precludes a clear understanding
of the directionality of these associations. For example, it remains possible that emotional
distress contributes to both cancer-related intrusive thoughts and perceptions of cancer
symptoms, course, and treatment as unclear and unpredictable. Because the association between
ambiguity and intrusive thoughts remained significant after adjusting for neuroticism, however,
an overall tendency to view things negatively likely did not fully account for this association.
Contrary to the hypothesis, neither the association between cancer-related ambiguity and
emotional distress nor the relation between ambiguity and intrusive thoughts depended on
whether a patient was intolerant of uncertainty. Similarly to cancer-related ambiguity, however,
intolerance of uncertainty was indirectly associated with emotional distress via its relation to
46
greater cancer-related ambiguity and intrusive thoughts. Because individuals who are highly
intolerant of uncertainty tend to approach ambiguous situations in an inflexible and negative
manner, these patients may have had difficulty adapting their worldviews to be congruent with
the cancer experience or incorporating their understanding of mCRC into their existing mental
models (Buhr & Dugas, 2002; Dugas, Schwartz & Francis, 2004). This inflexibility may have
contributed to incomplete processing, marked by intrusive thoughts, and emotional distress. This
result is particularly interesting given neuroticism was included in the model, suggesting that the
general tendency to be in a negative mood state did not entirely account for this association.
Therefore, perceiving uncertainty as undesirable and threatening specifically may interfere with
cognitive processing and contribute to emotional distress in patients with mCRC, though
directionality cannot be identified in this cross-sectional study.
The second psychosocial factor hypothesized to partially explain the associations
between emotional distress and both physical symptoms and cancer related ambiguity was the
extent to which patients participated in social activities. Greater physical symptoms and cancer-
related ambiguity were predicted to be associated with greater emotional distress indirectly via
their associations with less participation in social activities.
As was predicted, patients who experienced more physical symptoms also engaged in
fewer social activities, which may have occurred for several related reasons. For example,
patients may have perceived some of the symptoms as embarrassing (Steginga et al., 2009) and
therefore avoided situations where others would be present. Indeed, 42% of the patients in this
sample reported feeling embarrassed about their bowel function. Additionally, patients enduring
more physical symptoms may have been concerned about overexerting themselves or engaging
in activities that required them to be away from the home in case of a symptom flare (Strang et
al., 1992).
47
Although patients with more physical symptoms participated in fewer social activities,
fewer activities did not account for the relation between physical symptoms and emotional
distress. Previous research has demonstrated an association between lower participation in social
activities and emotional distress in patients with cancer (Syrjala et al., 2010), but involvement in
social activities was not directly associated with emotional distress in this sample of patients with
mCRC. The extent to which the participants thought their mCRC and its treatment interfered
with their participation in social activities, however, was associated with greater emotional
distress . Ea c h pa ti e nt’s p re fe rr e d l evel of social activity is unclear, so it is possible that the
perception of interference or a perceived mismatch between ideal and actual activity level
contributes to greater distress instead of the frequency of behavior. It is also possible that
patients who were experiencing high levels of distress may have reported more interference
regardless of their actual behavior (Mausbach et al., 2011). Another possible reason why fewer
social activities were not linked to distress is that unhelpful questions or comments from friends
and family members or uncomfortable symptom flares while engaging in social activities may
have made these activities more anxiety provoking and less enjoyable for some patients.
Participating in these activities may therefore be differentially related to distress depending on
perceived level of enjoyability. Lastly, socioemotional selectivity theory (Carstensen, 1995)
suggests that as time horizons shrink because of aging or life-threatening medical conditions,
individuals tend to demonstrate a selective narrowing of social interaction in which they choose
to spend time with fewer, more familiar individuals. Therefore, it may have been more
im porta nt for the pa rticip a nts’ a djust ment to s pe nd ti me w it h a sele c t fe w importa nt pe ople
instead of frequently participating in social activities outside of the home.
Social activities may also not have been associated with emotional distress due to
measurement issues. The patients tended to participate in few social activities, suggesting a
48
possible floor effect. Lack of variance in this measure of social activities, therefore, may have
limited its predictive ability. Finally, although the scale was validated in a sample of patients
with cancer (Logsdon & Teri, 1997; Syrjala et al., 2010), the items (e.g., shopping with others)
may not have been fully appropriate to capture social participation for our sample of middle-aged
and older-adult patients with metastatic colorectal cancer.
A related explanation supported by results from the post-hoc analysis is that the role of
socia l ac ti vit ies in pa ti e nts’ e mot ional dis tre ss dep e nde d on their level of perceived social
support. For patients with high or average social support, involvement in social activities was
not related to emotional distress. For patients who reported low social support, however, less
participation in social activities was associated with greater emotional distress. Perhaps if
patients were able to obtain adequate social support without engaging in social activities, then
their participation in these activities became less important. Those patients who did not have
sufficient social support, however, may have preferred engaging in social activities or had a
greater need to participate in them in order to buffer their emotional distress.
I n ge ne r a l, neither p e rc e ivi ng one ’s c a n c e r a s amb ig uous nor ha vin g dif fic u lt y tol e ra ti n g uncertainty was directly related to the extent to which patients engaged in social activities.
Contrary to the hypothesis, in patients reporting low levels of intolerance of uncertainty, viewing
the cancer experience as ambiguous was associated with less participation in social activities.
The beliefs that physical symptoms may flare unpredictably and that functional capabilities often
fluctuate could interfere with scheduling of social activities and raise concerns about how others
mi g ht per c e ive one ’s s y mpt oms, ther e for e r e duc i ng the likelihood of soc i a l enga g e ment (Persson
& Hellström, 2002). If patients are not experiencing high levels of intolerance of uncertainty,
they may not feel the need to seek comfort and reassurance from their social networks and the
potential costs of participating in these activities may outweigh the gains (Cougle et al., 2012).
49
R e late dl y , p a ti e nts’ f rie n ds an d fa mi l y m e mber s ma y h a ve ha d mor e diff i c ult y c opin g than th e patients. The patients who were highly intolerant of uncertainty might have been avoiding
situations in which comments from the anxious members of their social networks could
negatively impact their emotional well-being (Banthia et al., 2003; Pitceathly & Maguire, 2003).
The study hypotheses were tested while adjusting for neuroticism in order to help to
distinguish between (1) the overall tendency to experience distress and reporting distress in the
particular context of mCRC and (2) the tendency to be rigid and negative in general and
intolerance of uncertainty specifically. Because patients present with varying degrees of
neuroticism in the clinical setting, the hypotheses were also tested without adjusting for
neuroticism. Results were similar in this analysis, though the explained variance in emotional
distress decreased as expected with the removal of neuroticism.
One advantage of this study is that the hypotheses were tested in one model so that the
interrelations among the constructs as they relate to emotional distress could be more clearly
understood. Having intrusive thoug hts about one ’s mC R C a ppe a rs to pla y a ke y r ole in the
experience of greater emotional distress. Greater physical symptoms, cancer-related ambiguity,
and intolerance of uncertainty all demonstrated indirect associations with emotional distress via
their relations with greater intrusive thoughts. In other words, one of the reasons cancer-related
issues (i.e., physical symptoms and ambiguity) and the tendency to perceive uncertainty as
unacceptable or threatening are associated with greater emotional distress may be that they
require ongoing cognitive processing of cancer-related information, marked by intrusive
thoughts. Engaging in fewer social activities only appears to be relevant to emotional distress for
those patients who report low levels of social support. Although more research is needed to
clarify the causal relationships among these variables, targeting cancer-related intrusive thoughts
in psychological interventions may help to reduce emotional distress in patients with mCRC.
50
Limitations and Strengths
Several potential limitations of this study should be considered when interpreting results
and can inform directions for future research. First, the directionality and causal nature of the
associations between physical symptoms, cancer-related ambiguity, intrusive thoughts, social
activities, and emotional distress cannot be determined with a cross-sectional, correlational
design. Significant indirect associations, however, provide preliminary evidence that cancer-
related intrusive thoughts are relevant to emotional distress as it relates to physical symptoms,
ambiguity, and intolerance of uncertainty. Relatedly, without assessment of emotional distress
prior to cancer diagnosis, it cannot be said whether coping with the illness contributed to the
development of distress or whether pre-existing depression or anxiety disorders are being
measured in the context of cancer and lead to poorer adjustment with cancer diagnosis and
treatment.
Second, given the nature of metastatic colorectal cancer, the sample of patients is
somewhat heterogeneous on some extraneous variables (e.g., age, tumor response to treatment),
all of which could not be controlled for statistically or experimentally given the sample size and
correlational design of this study. Although several demographic and medical variables were
tested as potential covariates, it is possible that unmeasured constructs (e.g., stage at original
cancer diagnosis, comorbid health conditions) could have influenced the results. Because the
same medical team treated all of the patients in a single clinic, some of the potential
heterogeneity of medical factors may have been reduced, increasing internal validity but
potentially reducing generalizability. Similarly, results from a homogenous sample including
mostly highly educated, married, Caucasian individuals may not generalize to other populations.
Third, the relatively small sample size of 102 patients may have limited the power to
detect small effects. To address this potential limitation, a partial least squares modeling analytic
51
technique was used because it is robust and recommended over covariance-based structural
equation modeling when testing associations between multiple variables in modest samples. Of
note, significant associations were found among variables with effect sizes ranging from small to
large (f
2
s = 0.04-0.32; Cohen, 1992) suggesting power may not have been a major limiting factor
for these results.
Fourth, although intrusive thoughts are often theorized to be a marker of incomplete
cognitive processing (Creamer, Burgess & Pattison, 1992; Lepore, Ragan, & Jones, 2000; Jim &
Jacobsen, 2008), cognitive processing was not observed directly. Thus, it cannot be said for
certain whether intrusive thoughts are occurring due to incomplete processing.
Despite these limitations, this study contains several strengths. First, it examined the
psychosocial adjustment of two highly understudied cancer patient populations, those with
metastatic cancer and those with colorectal cancer, who appear to have a different illness
experience than the more commonly studied patients with localized breast or prostate cancer.
Second, this study draws upon psychological theory to help inform the understanding of
adjustment to mCRC. Third, robust modeling analyses were used to test the hypotheses,
maximizing the power to detect significant associations and the likelihood of valid results. Lastly,
this study identified potentially modifiable psychosocial mediators (i.e., intrusive thoughts) and
moderators (i.e., intolerance of uncertainty) of the relation between cancer-related variables and
emotional distress and serves as the first step towards designing psychosocial interventions
a im e d to i mprove pa ti e nt s’ qua li t y of lif e .
Conclusions and Future Directions
This study is one of the first to consider the experience of patients with metastatic
colorectal cancer within a biopsychosocial context. Clinically, assumptions are often made that
because of the threatening nature of metastatic cancer it is normative or even unavoidable for
52
patients to have depression or anxiety. Although a sizeable minority of patients did report
emotional distress, it was far from a universal experience. Intrusive thoughts about the cancer
experience appear to play a pivotal role in the emotional distress of patients with mCRC, linking
physical symptoms, cancer-related ambiguity, and intolerance of uncertainty to emotional
distress. In other words, in addition to their direct relation to emotional distress, physical
symptoms are also linked to distress because they increase the likelihood that patients will
perceive their cancer experience as highly ambiguous. Ambiguity may then interfere with
cognitive processing, maintaining intrusive thoughts and contributing to emotional distress.
Given these findings, patients who perceive cancer to be highly ambiguous or who
generally perceive ambiguity to be threatening may benefit from several types of intervention.
One key goal of treatment could be assisting patients with distinguishing between the types of
ambiguity that can be addressed with additional information or clarification and other aspects
that may be inherent to the mCRC experience and not as readily eradicated with additional
information. Then, patients could learn how to flexibly apply strategies to assist with managing
both aspects of cancer-related ambiguity. Doctor-patient communication training and
informational aids about cancer symptoms, treatment options, and disease course may help
patients to clarify misinformation and reduce cancer-related ambiguity to the extent information
is available (Mishel et al., 2002; Stiegelis et al., 2004; Mishel et al., 2009).
For aspects of ambiguity that cannot be eliminated, patients who are highly intolerant of
uncertainty may benefit from interventions designed to increase their tolerance through the use
of cognitive-behavioral skills and mindfulness techniques (Bailey, Mishel, Belyea, Stewart, &
Mohler, 2004; Dugas & Ladouceur, 2000; Dugas et al., 2003; Ladouceur et al., 2000; Ladouceur
et al., 2004; van der Heiden et al., 2012; Antoni et al., 2009; Hoffman et al., 2012; Ott, Norris, &
Bauer-Wu, 2006). For example, Intolerance of Uncertainty Therapy (e.g., Ladouceur et al.,
53
2000; van der Heiden et al., 2012) originally developed for individuals with generalized anxiety
disorder, utilizes strategies such as cognitive restructuring and problem-orientation training to
help individuals reevaluate uncertainty as a normal part of their daily lives and focus on making
decisions and participating in everyday activities despite this uncertainty. This intervention has
been shown to reduce self-reported intolerance of uncertainty and emotional distress in
individuals with generalized anxiety disorder (van der Heiden et al., 2012) and may also be
helpful for patients with mCRC who perceive substantial cancer-related ambiguity or who are
highly intolerant of uncertainty. These interventions may help to disrupt the associations of
perceived cancer-related ambiguity and intolerance of uncertainty with intrusive thoughts by
increasing flexibility and facilitating integration of cancer-related information, thereby reducing
emotional distress.
Interventions such as Cognitive Processing Therapy (Resick, Monson & Chard, 2008)
could also target intrusive thoughts regarding the mCRC experience more directly by assisting
the patients to process and express their thoughts and feelings about their cancer and reduce
emotional avoidance. Future research should examine the efficacy of this intervention in patients
with mCRC, particularly in those patients who are highly intolerant of uncertainty or view
mCRC as highly ambiguous.
Because lower social activity was associated with emotional distress in patients with low
social support, these patients in particular may benefit from behavioral activation interventions.
These interventions are designed to help them actively cope with a reduction in social activities
outside the home by replacing them with enjoyable, rewarding, and fulfilling social activities that
may be less impacted by their physical symptoms. These patients could be taught to better
communicate their needs with their social network, incorporate pacing strategies to limit
overexertion, and problem-solve for how they might cope with symptoms flares. It may also be
54
helpful to teach them cognitive restructuring in addition to this behavioral intervention so that
they can form a more balanced view of their physical limitations and potential for embarrassing
or uncomfortable interactions with their social networks.
Future research projects should test the efficacy of these types of interventions in
reducing the emotional distress in patients with mCRC, particularly those with substantial
physical symptoms or cancer-related ambiguity. It might be informative to include partners or
primary caregivers in future research in order to examine how their intolerance of uncertainty,
perceptions of cancer-related ambiguity, and e mot ional dis tre ss i nter a c t wit h the pa ti e nt’s
characteristics in their effects on emotional distress and relationship quality. Although
longitudinal research is needed to clarify the directionality and causality of observed
relationships, this study identified potential cancer-related and psychosocial risk factors that may
contribute to emotional distress in this patient population.
Overall, physicians and medical staff who treat patients with mCRC should not assume
that emotional distress is a normative experience for patients with mCRC. Taking an integrative
approach to assessment and treatment that considers biological, psychological, and social issues
may help to identify patients at increased risk for distress. These patients can then be referred to
psychopharmacological and psychological interventions that will assist with the primary goal of
tre a tm e nt for mC R C , im pr oving p a ti e nts’ qua li t y of li fe .

55
References
Aaronson, N. K., Ahmedzai, S., Bergman, B., Bullinger, M., Cull, A., Duez, N. J., Filiberti, A.,
et al. (1993). The European Organization for Research and Treatment of Cancer QLQ-
C30: a quality-of-life instrument for use in international clinical trials in oncology.
Journal of the National Cancer Institute, 85(5), 365 –376.
Alter, C. L., Pelcovitz, D., Axelrod, A., Goldenberg, B., Harris, H., Meyers, B., Grobois, B., et
al. (1996). Identification of PTSD in cancer survivors. Psychosomatics, 37(2), 137 –143.
Anagnostopoulos, F., Slater, J., & Fitzsimmons, D. (2010). Intrusive thoughts and psychological
adjustment to breast cancer: exploring the moderating and mediating role of global
meaning and emotional expressivity. Journal of Clinical Psychology in Medical Settings,
17(2), 137–149. doi:10.1007/s10880-010-9191-6
Antoni, M. H., Lechner, S., Diaz, A., Vargas, S., Holley, H., Phillips, K., McGregor, B., et al.
(2009). Cognitive behavioral stress management effects on psychosocial and
physiological adaptation in women undergoing treatment for breast cancer. Brain,
Behavior, and Immunity, 23(5), 580 –591. doi:10.1016/j.bbi.2008.09.005
Aranda, S., Schofield, P., Weih, L., Yates, P., Milne, D., Faulkner, R., & Voudouris, N. (2005).
Mapping the quality of life and unmet needs of urban women with metastatic breast
cancer. European Journal of Cancer Care, 14(3), 211 –222. doi:10.1111/j.1365-
2354.2005.00541.x
Arraras Urdaniz, J. I., Vera García, R., Martínez Aguillo, M., Manterola Burgaleta, A., Arias de
la Vega, F., & Salgado Pascual, E. (2006). Quality of Life assessment through the
EORTC questionnaires of colorectal cancer patients in advanced disease stages. Clinical
& Translational Oncology: Official Publication of the Federation of Spanish Oncology
Societies and of the National Cancer Institute of Mexico, 8(9), 664–671.
56
Badr, H., Carmack, C. L., Kashy, D. A., Cristofanilli, M., & Revenson, T. A. (2010). Dyadic
coping in metastatic breast cancer. Health Psychology: Official Journal of the Division of
Health Psychology, American Psychological Association, 29(2), 169–180.
doi:10.1037/a0018165
Bailey, D. E., Jr, Wallace, M., Latini, D. M., Hegarty, J., Carroll, P. R., Klein, E. A., &
Albertsen, P. C. (2011). Measuring illness uncertainty in men undergoing active
surveillance for prostate cancer. Applied Nursing Research: ANR, 24(4), 193 –199.
doi:10.1016/j.apnr.2009.08.001
Barnes, E. A., & Bruera, E. (2002). Fatigue in patients with advanced cancer: a review.
International Journal of Gynecological Cancer: Official Journal of the International
Gynecological Cancer Society, 12(5), 424 –428.
Baron, R. M., & Kenny, D. A. (1986). The moderator –mediator variable distinction in social
psychological research: Conceptual, strategic, and statistical considerations. Journal of
Personality and Social Psychology, 51, 1173–1182. doi:10.1037/0022-3514.51.6.1173
Bjelland, I., Dahl, A. A., Haug, T. T., & Neckelmann, D. (2002). The validity of the Hospital
Anxiety and Depression Scale. An updated literature review. Journal of Psychosomatic
Research, 52(2), 69 –77.
Bower, J.E. (2007). Cancer-related fatigue: Links with inflammation in cancer patients and
survivors. Brain, Behavior, and Immunity, 21(7), 863-871.
Brown, L. F., Kroenke, K., Theobald, D. E., Wu, J., & Tu, W. (2010). The association of
depression and anxiety with health-related quality of life in cancer patients with
depression and/or pain. Psycho-Oncology, 19(7), 734 –741. doi:10.1002/pon.1627
Buhr, K., & Dugas, M. J. (2002). The Intolerance of Uncertainty Scale: psychometric properties
of the English version. Behaviour Research and Therapy, 40(8), 931–945.
57
Carleton, R.N., Mulvogue, M.K., Thibodeau, M.A., McCabe, R.E., Antony, M.M. &
Asmundson, G.J.G. (2012). Increasingly certain about uncertainty: Intolerance of
uncertainty across anxiety and depression. Journal of Anxiety Disorders, 26(3), 468-479.
Carrato, A., Swieboda-Sadlej, A., Staszewska-Skurczynska, M., Lim, R., Roman, L., Shparyk,
Y., Bondarenko, I., et al. (2013). Fluorouracil, Leucovorin, and Irinotecan Plus Either
Sunitinib or Placebo in Metastatic Colorectal Cancer: A Randomized, Phase III Trial.
Journal of Clinical Oncology, 31(10), 1341 –1347. doi:10.1200/JCO.2012.45.1930
Carrato, A., Swieboda-Sadlej, A., Staszewska-Skurczynska, M., Lim, R., Roman, L., Shparyk,
Y., Bondarenko, I., et al. (2013). Fluorouracil, Leucovorin, and Irinotecan Plus Either
Sunitinib or Placebo in Metastatic Colorectal Cancer: A Randomized, Phase III Trial.
Journal of Clinical Oncology, 31(10), 1341 –1347. doi:10.1200/JCO.2012.45.1930
Carstensen, L.L. (1995). Evidence for a life-span theory of socioemotional selectivity. Current
Directions in Psychological Science, 4(5), 151-156.
Cella, D., Davis, K., Breitbart, W., & Curt, G. (2001). Cancer-related fatigue: prevalence of
proposed diagnostic criteria in a United States sample of cancer survivors. Journal of
Clinical Oncology: Official Journal of the American Society of Clinical Oncology,
19(14), 3385 –3391.
Cella, D. F., & Cherin, E. A. (1988). Quality of life during and after cancer treatment.
Comprehensive Therapy, 14(5), 69 –75.
Chen, C. Y., & Hong, R. Y. (2010). Intolerance of uncertainty moderates the relation between
negative life events and anxiety. Personality and Individual Differences, 49(1), 49 –53.
doi:10.1016/j.paid.2010.03.006
Chin, W. W., Marcolin, B. L., & Newsted, P. R. (2003). A partial least squares latent variable
modeling approach for measuring interaction effects: Results from a Monte Carlo
58
simulation study and an electronic-mail emotion/adoption study. Information Systems
Research, 14(2), 189 –217.
Christman, N.J. & Cain, L.B. (2004). The effects of concrete objective information and
relaxation on maintaining usual activity during radiation therapy. Oncology Nursing
Forum, 31(2), E39-E45.
Conroy, T., Bleiberg, H., & Glimelius, B. (2003). Quality of life in patients with advanced
colorectal cancer: what has been learnt? European Journal of Cancer (Oxford, England:
1990), 39(3), 287–294.
Cordova, M. J., Cunningham, L. L., Carlson, C. R., & Andrykowski, M. A. (2001). Social
constraints, cognitive processing, and adjustment to breast cancer. Journal of Consulting
and Clinical Psychology, 69(4), 706–711.
Costa-Requena, G., Rodríguez, A., Fernández, R., Palomera, E., & Gil, F. L. (2011). Cognitive
processing variables in breast cancer: worry and distress at the end of treatment. Journal
of Cancer Education: The Official Journal of the American Association for Cancer
Education, 26(2), 375 –379. doi:10.1007/s13187-010-0140-8
Creamer, M., Burgess, P., & Pattison, P. (1992). Reaction to trauma: a cognitive processing
model. Journal of Abnormal Psychology, 101(3), 452 –459.
DeCosse, J. J., & Cennerazzo, W. J. (1997). Quality-of-life management of patients with
colorectal cancer. CA: A Cancer Journal for Clinicians, 47(4), 198–206.
Dehni, N., Tiret, E., Singland, J. D., Cunningham, C., Schlegel, R. D., Guiguet, M., & Parc, R.
(1998). Long-term functional outcome after low anterior resection: comparison of low
colorectal anastomosis and colonic J-pouch-anal anastomosis. Diseases of the Colon and
Rectum, 41(7), 817 –822; discussion 822 –823.
59
Devine, D., Parker, P. A., Fouladi, R. T., & Cohen, L. (2003). The association between social
support, intrusive thoughts, avoidance, and adjustment following an experimental cancer
treatment. Psycho-Oncology, 12(5), 453–462. doi:10.1002/pon.656
Dugas, M. J., Schwartz, A., & Francis, K. (2004). Brief Report: Intolerance of Uncertainty,
Worry, and Depression. Cognitive Therapy and Research, 28(6), 835 –842.
doi:10.1007/s10608-004-0669-0
Dunn, J., Lynch, B., Aitken, J., Leggett, B., Pakenham, K., & Newman, B. (2003). Quality of life
and colorectal cancer: a review. Australian and New Zealand Journal of Public Health,
27(1), 41 –53.
Dugas, M J, & Ladouceur, R. (2000). Treatment of GAD. Targeting intolerance of uncertainty in
two types of worry. Behavior Modification, 24(5), 635–657.
Dugas, M.J, Ladouceur, R., Léger, E., Freeston, M. H., Langlois, F., Provencher, M.D., &
Boisvert, J.M. (2003). Group cognitive-behavioral therapy for generalized anxiety
disorder: treatment outcome and long-term follow-up. Journal of Consulting and Clinical
Psychology, 71(4), 821 –825.
Dupont, A., Bower, J.E., Stanton, A.L., & Ganz, P.A. (2014). Cancer-related intrusive thoughts
predict behavioral symptoms following breast cancer treatment. Health Psychology,
33(2), 155-163.
Efficace, F., Innominato, P. F., Bjarnason, G., Coens, C., Humblet, Y., Tumolo, S., Genet, D., et
a l. (2008) . Va li da ti on of pa ti e nt’s se lf -reported social functioning as an independent
prognostic factor for survival in metastatic colorectal cancer patients: results of an
international study by the Chronotherapy Group of the European Organisation for
Research and Treatment of Cancer. Journal of Clinical Oncology: Official Journal of the
60
American Society of Clinical Oncology, 26(12), 2020 –2026.
doi:10.1200/JCO.2007.12.3117
Galloway, S. C., & Graydon, J. E. (1996). Uncertainty, symptom distress, and information needs
after surgery for cancer of the colon. Cancer Nursing, 19(2), 112 –117.
Gaudine, A., Sturge-Jacobs, M., & Kennedy, M. (2003). The experience of waiting and life
during breast cancer follow-up. Research and Theory for Nursing Practice, 17(2), 153–
168.
Germino, B.B., Mishel, M.H., Belyea, M., Harris, L., Ware, A., & Mohler, J. (1998). Uncertainty
in prostate cancer: Ethnic and family patterns. Cancer Practice, 6, 107-113.
Glimelius, B., Hoffman, K., Graf, W., Påhlman, L., & Sjödén, P. O. (1994). Quality of life
during chemotherapy in patients with symptomatic advanced colorectal cancer. The
Nordic Gastrointestinal Tumor Adjuvant Therapy Group. Cancer, 73(3), 556 –562.
Green, B. L., Rowland, J. H., Krupnick, J. L., Epstein, S. A., Stockton, P., Stern, N. M., Spertus,
I. L., et al. (1998). Prevalence of posttraumatic stress disorder in women with breast
cancer. Psychosomatics, 39(2), 102–111.
Greenberg, M. A. (1995). Cognitive Processing of Traumas: The Role of Intrusive Thoughts and
Reappraisals1. Journal of Applied Social Psychology, 25(14), 1262–1296.
doi:10.1111/j.1559-1816.1995.tb02618.x
Gupta, D., Lis, C. G., & Grutsch, J. F. (2007). The relationship between cancer-related fatigue
and patient satisfaction with quality of life in cancer. Journal of Pain and Symptom
Management, 34(1), 40 –47. doi:10.1016/j.jpainsymman.2006.10.012
Ha e nlein, M., & Ka plan, A. ( 2004) . A B e g inne r’ s Guide to P a rtial L e a st S qua res Analysis.
Understanding Statistics, 3(4), 283 –297.
61
Hinz, A., Singer, S. & Brahler, E. (2014). European reference values for the quality of life
questionnaire EORTC QLQ-C30: Results of a German investigation and a summarizing
analysis of six European general population normative studies. (Acta Oncologica), 1-8.
Hjermstad, M.J., Fayers, P.M., Bjordal, K., & Kaasa, S. (1998). Using reference data on quality
of life-the importance of adjusting for age and gender, exemplified by the EORTC-QLQ-
C30. European Journal of Cancer, 34(9), 1381-1389.
Hoffman, C.J., Ersser, S.J., Hopkinson, J.B., Nicholls, P.G., Harrington, J.E., & Thomas, P.W.
(2012). Effectiveness of mindfulness-based stress reduction in mood, breast- and
endocrine-related quality of life, and well-being in stage 0 to III breast cancer: A
randomized, controlled trial. Journal of Clinical Oncology, 30(12), 1335- 1342.
Hopwood, C. J. (2007). Moderation and Mediation in Structural Equation Modeling:
Applications for Early Intervention Research. Journal of Early Intervention, 29(3), 262 –
272. doi:10.1177/105381510702900305
Horowitz, M., Wilner, N., & Alvarez, W. (1979). Impact of Event Scale: a measure of subjective
stress. Psychosomatic Medicine, 41(3), 209–218.
Hulland, J. (1999). Use of partial least squares (PLS) in strategic management research: a review
of four recent studies. Strategic Management Journal, 20, 195–204.
doi:10.1002/(SICI)1097-0266(199902)20:2<195::AID-SMJ13>3.0.CO;2-7
Jim, H. S., Andrykowski, M. A., Munster, P. N., & Jacobsen, P. B. (2007). Physical
symptoms/side effects during breast cancer treatment predict posttreatment distress.
Annals of Behavioral Medicine, 34(2), 200 –208. doi:10.1007/BF02872674
Jim, H.S.L. & Jacobsen, P. B. (2008). Posttraumatic stress and posttraumatic growth in cancer
survivorship: A review. Cancer Journal (Sudbury, Mass.), 14(6), 414 –419.
doi:10.1097/PPO.0b013e31818d8963
62
Kaiser, H.F. (1970). A Second-Generation Little Jiffy. Psychometrika, 35(4), 401-15.
Kaiser H.F. (1974). Little Jiffy, Mark IV. Educational and Psychological Measurement, 34,
111-7.
Kindler, H. L., & Shulman, K. L. (2001). Metastatic colorectal cancer. Current Treatment
Options in Oncology, 2(6), 459 –471.
Klemm, P., Miller, M. A., & Fernsler, J. (2000). Demands of illness in people treated for
colorectal cancer. Oncology Nursing Forum, 27(4), 633–639.
Ladouceur, Robert, Léger, E., Dugas, M., & Freeston, M. H. (2004). Cognitive-behavioral
treatment of generalized anxiety disorder (GAD) for older adults. International
Psychogeriatrics / IPA, 16(2), 195 –207.
Ladouceur, R., Dugas, M.J., Freeston, M.H., Leger, E., Gagnon, F., & Thibodeau, N. (2000).
Efficacy of a cognitive-behavioral treatment for generalized anxiety disorder: Evaluation
in a controlled clinical trial. Journal of Consulting and Clinical Psychology, 68(6), 957-
964.
Laird, B. J. A., Boyd, A. C., Colvin, L. A., & Fallon, M. T. (2009). Are cancer pain and
depression interdependent? A systematic review. Psycho-Oncology. Vol 18(5), 18, 459–
464.
Lepore, S. J., Silver, R. C., Wortman, C. B., & Wayment, H. A. (1996). Social constraints,
intrusive thoughts, and depressive symptoms among bereaved mothers. Journal of
Personality and Social Psychology, 70(2), 271 –282.
Lesage, & Portenoy. (1999). Trends in Cancer Pain Management. Cancer Control: Journal of
the Moffitt Cancer Center, 6(2), 136–145.
63
Lewis, J. A., Manne, S. L., DuHamel, K. N., Vicksburg, S. M. J., Bovbjerg, D. H., Currie, V.,
Winkel, G., et al. (2001). Social support, intrusive thoughts, and quality of life in breast
cancer survivors. Journal of Behavioral Medicine. Vol 24(3), 24(2001), 231 –245.
Liao, M.N., Chen, M.F., Chen, S.C., & Chen, P.L. (2008). Uncertainty and anxiety during the
diagnostic period for women with suspected breast cancer. Cancer Nursing, 31(4), 274–
283. doi:10.1097/01.NCC.0000305744.64452.fe
Lien, C.Y., Lin, H.R., Kuo, I.T., & Chen, M.L. (2009). Perceived uncertainty, social support and
psychological adjustment in older patients with cancer being treated with surgery.
Journal of Clinical Nursing, 18(16), 2311 –2319.
Logsdon, R. G., & Teri, L. (1997). The Pleasant Events Schedule-AD: psychometric properties
a nd re lations hip t o de pr e ssi on a nd c og nit ion i n Al z he im e r’ s di se a se pa ti e nt s. The
Gerontologist, 37(1), 40 –45.
Lynch, B. M., Steginga, S. K., Hawkes, A. L., Pakenham, K. I., & Dunn, J. (2008). Describing
and predicting psychological distress after colorectal cancer. Cancer, 112(6), 1363 –1370.
doi:10.1002/cncr.23300
Macvean, M. L., White, V. M., Pratt, S., Grogan, S., & Sanson-Fisher, R. (2007). Reducing the
unmet needs of patients with colorectal cancer: a feasibility study of The Pathfinder
Volunteer Program. Supportive Care in Cancer: Official Journal of the Multinational
Association of Supportive Care in Cancer, 15(3), 293 –299. doi:10.1007/s00520-006-
0128-4
Majumdar, S. R., Fletcher, R. H., & Evans, A. T. (1999). How does colorectal cancer present?
Symptoms, duration, and clues to location. The American Journal of Gastroenterology,
94(10), 3039 –3045. doi:10.1111/j.1572-0241.1999.01454.x
64
Maughan, T. S., James, R. D., Kerr, D. J., Ledermann, J. A., McArdle, C., Seymour, M. T.,
Cohen, D., et al. (2002). Comparison of survival, palliation, and quality of life with three
chemotherapy regimens in metastatic colorectal cancer: a multicentre randomised trial.
Lancet, 359(9317), 1555 –1563.
Mausbach, B. T., Chattillion, E. A., Moore, R. C., Roepke, S. K., Depp, C. A., & Roesch, S.
(2011). Activity restriction and depression in medical patients and their caregivers: a
meta-analysis. Clinical Psychology Review, 31(6), 900 –908.
doi:10.1016/j.cpr.2011.04.004
Mausbach, B. T., Roepke, S. K., Depp, C. A., Moore, R., Patterson, T. L., & Grant, I. (2011).
Integration of the pleasant events and activity restriction models: development and
va li da ti on of a “ P EAR” model of ne g a ti ve outco mes in Alz he im e r’ s ca r e g iver s. Behavior
Therapy, 42(1), 78 –88. doi:10.1016/j.beth.2009.11.006
Medeiros, M., Oshima, C. T. F., & Forones, N. M. (2010). Depression and anxiety in colorectal
cancer patients. Journal of Gastrointestinal Cancer, 41(3), 179–184.
doi:10.1007/s12029-010-9132-5
Mehnert, A. & Koch, U. (2007). Prevalence of acute and post-traumatic stress disorder and
comorbid mental disorders in breast cancer patients during primary cancer care: A
prospective study. Psycho-oncology, 16(3), 181-188.
Miller, A.H., Ancoli-Israel, S., Bower, J.E., Capuron, L. & Irwin, M.R. (2008). Neuroendocrine-
immune mechanisms of behavioral comorbidities in patients with cancer. Journal of
Clinical Oncology, 26(6), 971-982.
Mishel, M. H. (1981). The measurement of uncertainty in illness. Nursing Research, 30(5), 258 –
263.
65
Mishel, M. H. (1997). Uncertainty in acute illness. Annual Review of Nursing Research, 15, 57–
80.
Mishel, M. H. (1999). Uncertainty in chronic illness. Annual Review of Nursing Research, 17,
269–294.
Mishel, M.H., Belyea, M., Germino, B.B., Stewart, J.L., Bailey, D.E., Robertson, C., & Mohler,
J. (2002). Helping patients with localized prostate carcinoma manage uncertainty and
treatment side effects. Cancer, 94(6), 1854-1866
Mishel, M.H., Germino, B.B., Lin, L., Pruthi, R.S., Wallen, E.M., Crandell, J., & Blyler, D.
(2009). Managing uncertainty about treatment decision making in early stage prostate
cancer: A randomized clinical trial. Patient Education and Counseling, 77, 349-359.
Mock, V., Atkinson, A., Barsevick, A., Cella, D., Cimprich, B., Cleeland, C., Donnelly, J., et al.
(2000). NCCN Practice Guidelines for Cancer-Related Fatigue. Oncology (Williston
Park, N.Y.), 14(11A), 151 –161.
Morrow, G. R., Andrews, P. L. R., Hickok, J. T., Roscoe, J. A., & Matteson, S. (2002). Fatigue
associated with cancer and its treatment. Supportive Care in Cancer: Official Journal of
the Multinational Association of Supportive Care in Cancer, 10(5), 389 –398.
doi:10.1007/s005200100293
Munch, T. N., Strömgren, A. S., Pedersen, L., Petersen, M. A., Hoermann, L., & Groenvold, M.
(2006). Multidimensional measurement of fatigue in advanced cancer patients in
palliative care: an application of the multidimensional fatigue inventory. Journal of Pain
and Symptom Management, 31(6), 533 –541. doi:10.1016/j.jpainsymman.2005.11.012
Murata, A., Brown, C. J., Raval, M., & Phang, P. T. (2008). Impact of short-course radiotherapy
and low anterior resection on quality of life and bowel function in primary rectal cancer.
66
American Journal of Surgery, 195(5), 611–615; discussion 615.
doi:10.1016/j.amjsurg.2007.12.034
Neuman, H. B., Schrag, D., Cabral, C., Weiser, M. R., Paty, P. B., Guillem, J. G., Minsky, B. D.,
et al. (2007). Can differences in bowel function after surgery for rectal cancer be
identified by the European Organization for Research and Treatment of Cancer quality of
life instrument? Annals of Surgical Oncology, 14(5), 1727 –1734. doi:10.1245/s10434-
006-9283-6
Northouse, L. L., Mo od, D., T e mpl in, T., Mellon, S ., & Ge or ge , T. ( 2000) . C ouples’ pa tt e rns of adjustment to colon cancer. Social Science & Medicine (1982), 50(2), 271 –284.
Northouse, L. L., Schafer, J. A., Tipton, J., & Metivier, L. (1999). The concerns of patients and
spouses after the diagnosis of colon cancer: a qualitative analysis. Journal of Wound,
Ostomy, and Continence Nursing: Official Publication of The Wound, Ostomy and
Continence Nurses Society / WOCN, 26(1), 8 –17.
Nor um, J . ( 1997) . Adjuva nt che mot he r a p y in Duk e s’ B and C colorectal cancer has only a minor
influence on psychological distress. Supportive Care in Cancer: Official Journal of the
Multinational Association of Supportive Care in Cancer, 5(4), 318–321.
Osborne, J.W. and Costello, A.B. (2005). Recommendations for getting the most from your
analysis. Practical Assessment, Research & Evaluation, 10(7), 1-9.
Ott, M. J., Norris, R. L., & Bauer-Wu, S. M. (2006). Mindfulness meditation for oncology
patients: a discussion and critical review. Integrative Cancer Therapies, 5(2), 98 –108.
doi:10.1177/1534735406288083
Palmer, G., Martling, A., Lagergren, P., Cedermark, B., & Holm, T. (2008). Quality of life after
potentially curative treatment for locally advanced rectal cancer. Annals of Surgical
Oncology, 15(11), 3109 –3117. doi:10.1245/s10434-008-0112-y
67
Pan, L.-H., Tsai, Y.-F., Chen, M.-L., Tang, R., & Chang, C.-J. (2011). Symptom distress and
self-care strategies of colorectal cancer patients with diarrhea up to 3 months after
surgery. Cancer Nursing. Vol 34(1), 34(2011), E1 –E9.
Peeters, K. C. M. J., van de Velde, C. J. H., Leer, J. W. H., Martijn, H., Junggeburt, J. M. C.,
Kranenbarg, E. K., Steup, W. H., et al. (2005). Late side effects of short-course
preoperative radiotherapy combined with total mesorectal excision for rectal cancer:
increased bowel dysfunction in irradiated patients--a Dutch colorectal cancer group
study. Journal of Clinical Oncology: Official Journal of the American Society of Clinical
Oncology, 23(25), 6199 –6206. doi:10.1200/JCO.2005.14.779
Persson, E., & Hellström, A.-L. (2002). Experiences of Swedish men and women 6 to 12 weeks
after ostomy surgery. Journal of Wound, Ostomy, and Continence Nursing: Official
Publication of The Wound, Ostomy and Continence Nurses Society / WOCN, 29(2), 103 –
108.
Primo, K., Compas, B. E., Oppedisano, G., Howell, D. C., Epping-Jordan, J. E., & Krag, D. N.
(2000). Intrusive thoughts and avoidance in breast cancer: Individual differences and
associations with psychological distress. Psychology & Health. Vol 14(6), 14(2000),
1141–1153.
Radloff, L. S. (1977). The CES-D Scale: A Self-Report Depression Scale for Research in the
General Population. Applied Psychological Measurement, 1(3), 385–401.
doi:10.1177/014662167700100306
Reddick, B. K., Nanda, J. P., Campbell, L., Ryman, D. G., & Gaston-Johansson, F. (2005).
Examining the influence of coping with pain on depression, anxiety, and fatigue among
women with breast cancer. Journal of Psychosocial Oncology, 23(2-3), 137 –157.
68
Resick, P.A., Monson, C.M., & Chard, K.M. (2008). Cognitive processing therapy:
Ve ter a n/m il it a r y ve rsion. W a shing ton, DC : De pa rt ment of Ve ter a ns’ A ff a ir s.
Rich, T., Innominato, P.F., Boerner, J., Mormont, M.C., Iacobelli, S., Baron, B., Jasmin, C., &
Levi, F. (2005). Elevated serum cytokines correlated with altered behavior, serum
cortisol rhythm, and dampened 24-hour rest-activity patterns in patients with metastatic
colorectal cancer. Clinical Cancer Research, 11, 1757-1764,
Schwenk, W., Böhm, B., & Müller, J. M. (1998). Postoperative pain and fatigue after
laparoscopic or conventional colorectal resections. A prospective randomized trial.
Surgical Endoscopy, 12(9), 1131 –1136.
Shaha, M., & Cox, C. L. (2003). The omnipresence of cancer. European Journal of Oncology
Nursing: The Official Journal of European Oncology Nursing Society, 7(3), 191 –196.
Shaha, M., Cox, C. L., Talman, K., & Kelly, D. (2008). Uncertainty in breast, prostate, and
colorectal cancer: implications for supportive care. Journal of Nursing Scholarship: An
Official Publication of Sigma Theta Tau International Honor Society of Nursing / Sigma
Theta Tau, 40(1), 60 –67. doi:10.1111/j.1547-5069.2007.00207.x
Simon, A. E., Thompson, M. R., Flashman, K., & Wardle, J. (2009). Disease stage and
psychosocial outcomes in colorectal cancer. Colorectal Disease: The Official Journal of
the Association of Coloproctology of Great Britain and Ireland, 11(1), 19 –25.
doi:10.1111/j.1463-1318.2008.01501.x
Smith, E. M., Gomm, S. A., & Dickens, C. M. (2003). Assessing the independent contribution to
quality of life from anxiety and depression in patients with advanced cancer. Palliative
Medicine, 17(6), 509 –513.
69
Sprangers, M. A., Taal, B. G., Aaronson, N. K., & te Velde, A. (1995). Quality of life in
colorectal cancer. Stoma vs. nonstoma patients. Diseases of the Colon and Rectum, 38(4),
361–369.
Stegelis, H.E., Hagedoorn, M., Sanderman, R., Bennenbroek, F.T.C., Buunk, B.P., Van Den
Bergh, A.C.M., Botke, G., & Ranchor, A.V. (2004). The impact of an informational self-
management intervention on the association between control and illness uncertainty
before and psychological distress after radiotherapy. Psycho-Oncology, 13, 248-259.
Steginga, S. K., Lynch, B. M., Hawkes, A., Dunn, J., & Aitken, J. (2009). Antecedents of
domain-specific quality of life after colorectal cancer. Psycho-Oncology, 18(2), 216–220.
doi:10.1002/pon.1388
Strang, P. (1992). Emotional and social aspects of cancer pain. Acta Oncologica (Stockholm,
Sweden), 31(3), 323 –326.
Syrjala, K. L., Stover, A. C., Yi, J. C., Artherholt, S. B., & Abrams, J. R. (2010). Measuring
social activities and social function in long-term cancer survivors who received
hematopoietic stem cell transplantation. Psycho-Oncology, 19(5), 462–471.
doi:10.1002/pon.1572
Tavoli, A., Mohagheghi, M. A., Montazeri, A., Roshan, R., Tavoli, Z., & Omidvari, S. (2007).
Anxiety and depression in patients with gastrointestinal cancer: does knowledge of
cancer diagnosis matter? BMC Gastroenterology, 7, 28. doi:10.1186/1471-230X-7-28
Temple, L. K., Bacik, J., Savatta, S. G., Gottesman, L., Paty, P. B., Weiser, M. R., Guillem, J.
G., et al. (2005). The development of a validated instrument to evaluate bowel function
after sphincter-preserving surgery for rectal cancer. Diseases of the Colon and Rectum,
48(7), 1353–1365. doi:10.1007/s10350-004-0942-z
70
Tol, J., Koopman, M., Cats, A., Rodenburg, C. J., Creemers, G. J. M., Schrama, J. G., Erdkamp,
F. L. G., et al. (2009). Chemotherapy, bevacizumab, and cetuximab in metastatic
colorectal cancer. The New England Journal of Medicine, 360(6), 563 –572.
doi:10.1056/NEJMoa0808268
Tsunoda, A., Nakao, K., Hiratsuka, K., Yasuda, N., Shibusawa, M., & Kusano, M. (2005).
Anxiety, depression and quality of life in colorectal cancer patients. International Journal
of Clinical Oncology / Japan Society of Clinical Oncology, 10(6), 411 –417.
doi:10.1007/s10147-005-0524-7
van der Heiden, C., Muris, P., & van der Molen, H. T. (2012). Randomized controlled trial on
the effectiveness of metacognitive therapy and intolerance-of-uncertainty therapy for
generalized anxiety disorder. Behaviour Research and Therapy, 50(2), 100 –109.
doi:10.1016/j.brat.2011.12.005
Vinzi, V. E., Chin, W. W., & Henseler, J. (2009). Handbook of partial least squares: concepts,
methods and applications. Springer.
Wallace, M. (2003). Uncertainty and quality of life of older men who undergo watchful waiting
for prostate cancer. Oncology Nursing Forum, 30(2), 303–309. doi:10.1188/03.ONF.291-
300
Warren, M. (2010). Uncertainty, lack of control and emotional functioning in women with
metastatic breast cancer: a review and secondary analysis of the literature using the
critical appraisal technique. European Journal of Cancer Care, 19(5), 564 –574.
doi:10.1111/j.1365-2354.2010.01215.x
Weiser, M. R., Quah, H.-M., Shia, J., Guillem, J. G., Paty, P. B., Temple, L. K., Goodman, K.
A., et al. (2009). Sphincter preservation in low rectal cancer is facilitated by preoperative
71
chemoradiation and intersphincteric dissection. Annals of Surgery, 249(2), 236 –242.
doi:10.1097/SLA.0b013e318195e17c
Weiss, D. S. (2007). The Impact of Event Scale: Revised. In J. P. Wilson & C. S. Tang (Eds.),
Cross-Cultural Assessment of Psychological Trauma and PTSD (pp. 219 –238). Boston,
MA: Springer US. Retrieved from http://www.springerlink.com/index/10.1007/978-0-
387-70990-1_10
Weissman, M. M., Sholomskas, D., Pottenger, M., Prusoff, B. A., & Locke, B. Z. (1977).
Assessing depressive symptoms in five psychiatric populations: a validation study.
American Journal of Epidemiology, 106(3), 203 –214.
Whistance, R. N., Conroy, T., Chie, W., Costantini, A., Sezer, O., Koller, M., Johnson, C. D., et
al. (2009). Clinical and psychometric validation of the EORTC QLQ-CR29 questionnaire
module to assess health-related quality of life in patients with colorectal cancer.
European Journal of Cancer (Oxford, England: 1990), 45(17), 3017–3026.
doi:10.1016/j.ejca.2009.08.014
Whitaker, K. L., Brewin, C. R., & Watson, M. (2008). Intrusive cognitions and anxiety in cancer
patients. Journal of Psychosomatic Research, 64(5), 509 –517.
doi:10.1016/j.jpsychores.2008.02.009
Whynes, D. K., & Neilson, A. R. (1997). Symptoms before and after surgery for colorectal
cancer. Quality of Life Research: An International Journal of Quality of Life Aspects of
Treatment, Care and Rehabilitation, 6(1), 61 –66.
Wallace, M. (2005). Finding more meaning: the antecedents of uncertainty revisited. Journal of
Clinical Nursing, 14(7), 863 –868. doi:10.1111/j.1365-2702.2005.01138.x
Williamson, G. M., & Shaffer, D. R. (2000). The activity restriction model of depressed affect:
Antecedents and consequences of restricted normal activities. In G. M. Williamson, D. R.
72
Shaffer, & P. A. Parmelee (Eds.), Physical illness and depression in older adults: A
handbook of theory, research, and practice (pp. 173 –200). Kluwer Academic/Plenum.
Wong, C. A., & Bramwell, L. (1992). Uncertainty and anxiety after mastectomy for breast
cancer. Cancer Nursing, 15(5), 363 –371.
Zigmond, A. S., & Snaith, R. P. (1983). The hospital anxiety and depression scale. Acta
Psychiatrica Scandinavica, 67(6), 361 –370.

73
Table 1
Descriptive statistics for demographic and medical variables

Demographic
variables
N=102
Gender 52% Female
48% Male

Marital Status 17% Single
83% Married/Partnered

Highest Education 0 % Grade School
3 % Some High School
16% High School or GED
7% Vocational
24% Associates Degree
26% Bachelors Degree
14% Masters
11% Doctorate

Income 13% < 20,000
17% 20,001-50,000
14% 50,001-80,000
19% 80,001-110,000
10% 110,001-140,000
7% 140,001-170,000
4% 17,001-200,000
16% over 200k

Ethnicity 3% African American
13% Hispanic
12% Asian
67% Caucasian
5% Other

Age M = 55.07, SD = 11.24, Observed range: 29-83

Medical variables

Primary cancer site 66% Colon
34% Rectum

Months since
diagnosis with
M = 26.77, SD = 31.77, Observed range: 0-170 months
74

metastatic disease

Treatment Chemo
94% current
6% past
Radiation
1% current
25% past
2% Targeted therapy
81% Surgery

Stoma 21% Yes
79% No

Number of regimens
of different
chemotherapy
medications
17% 1 line
25% 2 lines
35% 3 lines
13% 4 lines
8% 5 lines
2% 6 lines

Tumor Response
(RECIST score)
10% Complete Response
21% Partial Response
34% Stable Disease
35% Progressive Disease
75
Table 2
Regression modeling predicting depression, anxiety, and emotional dysfunction for covariate
identification

Depression
B ( S E ), β
Anxiety
B ( S E ), β
Emotional Dysfunction
B ( S E ), β

Male -1.64 (1.55), -0.11 -0.64 (0.70), -0.10 0.002, (0.12), 0.002
Partnered -3.15 (2.13), -0.16 -0.67 (0.96), -0.79 -0.14 (0.16), -0.09
Income -0.03 (0.38), -0.01 -0.11 (0.17), -0.08 -0.01 (0.03), -0.05
Caucasian -2.65 (1.59), -0.17 0.24 (0.72), 0.03 -0.07 (0.12), -0.06
Age -0.00 (0.07), -0.01 -0.05 (0.03), -0.19 0 (0.005), 0
Months since
mCRC
diagnosis
-0.03 (0.02), -0.23 -0.01(0.01), -0.05 -0.004 (0.002), -0.20*
Radiation -3.86 (1.61), -0.23* -0.43 (0.73), -0.06 -0.19 (0.12), -0.14
Surgery 0.86 (2.04), 0.04 0.79 (0.92), 0.09 0.30 (0.15), -0.17
x
Tumor
response
(RECIST
score)
-0.39 (0.76), -0.05 0.38 (0.34), 0.11 -0.06 (0.57), -0.10
Neuroticism 1.26 (0.26), 0.49*** 0.52 (0.12), 0.47*** 0.13 (0.02), 0.60***

x
p < 0.10, * p < 0.05, ** p < 0.01, *** p < 0.001

76
Table 3
Factor loadings from exploratory factor analysis for Memorial Sloan Kettering Cancer Center-
Bowel Function Instrument (N=102)

Item Loading
Have you had to alter your activities because of your bowel function? .771

Have you had soilage (leakage of stool) of your undergarments when you go to
bed?
.754

Have you had soilage (leakage of stool) of your undergarments during the day? .726
Have you had diarrhea (no form, watery stool)? .621

Did you get to the toilet on time? .603

Have you used a tissue, napkin, and/or pad in your undergarments during the
day in case of stool leakage?
.576

Have you been able to wait 15 minutes to get to the toilet when you feel like you
are going to have a bowel movement?
.545
Did you know the difference between having to pass gas and needing to have a
bowel movement?
.537

Have you been able to control the passage of gas (air)? .505

Did you have another bowel movement within 15 minutes of your last bowel
movement?
.504

Have you limited the types of liquids you drink to control your bowel
movements?
.487

Have you used medicines to decrease the number of bowel movements (e.g.
Imodium, Lomotil)
.481

Have you limited the types of solid food you eat to control your bowel
movements?
.440

Have you had loose stool (slight form, but mushy)? .417

Did you feel like you had totally emptied your bowels after a bowel movement? .405
77
Table 4
Factor loadings from exploratory factor analysis for MUIS Ambiguity subscale (N=102)

Item Loading
It is not clear what is going to happen to me. .659
It is unclear how bad my pain will be. .645

I am unsure if my illness is getting better or worse. .637
Because of the unpredictability of my illness, I cannot plan for the future. .626

My symptoms continue to change unpredictably. .614
It is difficult to determine how long it will be before I can care for myself. .613

It is difficult to know if the treatments or medications I am getting are
helping.
.594

The effectiveness of the treatment is undermined. .564
I t’s v a g ue to m e how I will manage my care. .552
The course of my illness keeps changing. I have good days and bad days. .496

Because of the treatment, what I can do and cannot do keeps changing. .481

I do not know when to expect things will be done to me. .473
My treatment is too complex to figure out. .406

78
Table 5
Factor loadings from exploratory factor analysis for non-somatic CES-D (N=102)

Item Loading
I felt sad .857

I felt that I could not shake off the blues even with help from
my family and friends
.695

I felt lonely .667

I felt depressed .650

I felt fearful .646

I had crying spells .617

I talked less than usual .615

I was happy .491

I thought my life had been a failure .481

People were unfriendly .461

I had trouble keeping my mind on what I was doing .441
I felt like I was just as good as other people .418

I enjoyed life .372

I felt that people disliked me .334

I felt hopeful about the future

.322

79
Table 6
Factor loadings from exploratory factor analysis for HADS-A (N=102)

Item Loading
Worrying thoughts go through my mind .714

I got sort of frightened feeling as if something awful is about to happen .710
I get sudden feelings of panic .667

I get a sort of frightened feeling like butterflies in my stomach .610
I can sit at ease and feel relaxed .404

I feel tense or wound up .356

I feel restless as if I have to be on the move .347

80
Table 7
Factor loadings from exploratory factor analysis for EORTC-QLQ-C30 emotional dysfunction
subscale (N=102)

Item Loading
Did you feel tense .767

Did you worry .725

Did you feel irritable .689

Did you feel depressed .610

81
Table 8
Factor loadings from exploratory factor analysis for IES-R Intrusive Thoughts subscale (N=102)

Item Loading
I had waves of strong feelings about it .787

I thou g ht about it whe n I didn’t m e a n to .774

Other things kept making me think about it .760

Any reminder brought back feelings about it .747

I found myself acting or feeling like I was back at that time .619
Pictures about it popped into my mind .565

I had trouble staying asleep .525

I had dreams about it .490

82
Table 9
Factor loadings from exploratory factor analysis for Social Activity Log Social Activities
subscale (N=102)

Item Loading
Eating a meal at a restaurant with others .704

Attending a party or social gathering .562

Attending a concert, theater, or other cultural or musical event with a friend,
family member, or acquaintance
.488
Seeing a movie in a theater with others .462

S hopping with ot he rs w h o don’ t l ive w it h y ou .425

Visiting the homes of my friends or acquaintances .418

Going to a sports game to watch with others .402

83
Table 10
Confirmatory factor analyses
χ
2
RMSEA CFI NNFI
Intolerance of
Uncertainty

1-Factor
Model
149.32 0.13 0.80 0.75

2-Factor
Model
125.45 0.11 0.85 0.81

84
Table 11
Factor loadings from exploratory factor analysis for Intolerance of Uncertainty Scale-Short
Form (N=102)
Factor loadings
Item Factor 1:
Uncertainty
interferes with
action
Factor 2:
Uncertainty is
upsetting
Factor 3:
Intolerance of
uncertainty
about the
future
W he n it ’s tim e to ac t, unce rta int y paralyses me.
0.936 -0.078 -0.017

The smallest doubt can stop me from
acting.
0.657 -0.147 0.122

W he n I a m un c e rt a in I c a n’ t func ti on
very well.
0.642 0.252 -0.200

A small, unforeseen event can spoil
everything, even with the best of
planning.
0.423 0.203 0.209

I must get away from all uncertain
situations.
0.418 0.156 0.160

Unforeseen events upset me greatly. -0.101 0.961 -0.017

Uncertainty keeps me from living a
full life.
0.195 0.770 -0.123

I c a n’ t st a nd b e ing t a ke n b y surp rise . 0.058 0.507 0.203

I should be able to organize everything
in advance.
0.136 -0.217 0.730

One should always look ahead so as to
avoid surprises.
-0.036 0.071 0.551

I always want to know what the future
has is store for me.
-0.178 0.276 0.483

It frustrates me not having all the
information I need.
0.034 0.197 0.456
85
Table 12
Descriptive statistics for key variables
Variable Mean (SD)/
Frequency
(%)
Possible
Range
Observed
Range
Pain 2.06(0.93) 1-4 1-4

Fatigue 2.71(0.77) 1-4 1-4

Bowel function 58.09(9.31) 15-75 24-74

Cancer-related ambiguity 34.20(8.96) 13-65 13-53

Anxiety 5.28(3.32) 0-21 0-13

Non-somatic depression 10.74(7.27) 0-45 0-32

Emotional dysfunction 2.03(0.60) 1-4 1-4

Intrusive thoughts 1.09(0.75) 0-4 0-3.13

Social activities 0.81(0.43) 0-4 0-1.86

Intolerance of uncertainty total 22.99(7.21) 12-60 12-42

IUS-SF: Inaction 7.72(3.10) 5-25 5-18

IUS-SF: Upsetting 6.75(2.74) 3-15 4-14

IUS-SF: Future 9.63(3.25) 4-20 4-18

Neuroticism 3.22(2.84) 0-12 0-11

Social support 4.33(0.70) 1-5 1.42-5

Social interference 2.52(0.51) 1-4 1-4
86
Table 13
Correlations of demographic, medical, and key study variables
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
1 Male 1.00
2 Married /
partnered
.17 1.00
3 College .01 .03 1.00
4 Income .06 .42** .30** 1.00
5 Caucasian .02 .15 .18 .35** 1.00
6 Age .25* -.05 -.31** -.14 .03 1.00
7 Cancer site .02 -.10 -.01 .004 -.07 .02 1.00
8 Months since
mCRC
diagnosis
.10 .05 -.03 .00 -.08 .13 .07 1.00
9 Radiation .04 -.04 -.08 -.09 -.15 .08 .46** .14 1.00
10 Surgery .07 .07 .00 -.08 -.11 .06 -.16 .27** .04 1.00
11 Stoma -.07 -.10 -.18 .01 -.07 .11 .41 -.06 .34** .13 1.00
12 Tumor response
(RECIST)
.06 -.04 -.15 -.13 -.08 .26* -.08 -.10 .18 -.07 .10 1.00
13 Neuroticism -.24* -0.09 .00 -.18 .08 -.02 -.06 -.04 .04 .13 -.08 .02 1.00
14 Depression -.30** -.19 -.13 -.22* -.08 -.08 -.08 -.14 -.18 .09 .06 -.01 .54** 1.00
15 Anxiety -.27** -.08 -.04 -.13 .08 -.13 -.03 -.12 -.02 .13 .14 .13 .55** .69** 1.00
16 Emotional
dysfunction
-.21* -.13 .04 -.20 .04 -.04 -.09 -.19 -.13 .21* .02 -.08 .64** .69** .72** 1.00
17 Fatigue -.07 .05 .02 -.13 .15 -.12 -.09 -.16 -.16 -.13 -.04 -.09 .15 .36** .31** .42** 1.00
18 Pain .04 .14 -.19 -.01 .03 -.07 -.02 .00 -.09 -.08 .13 .15 -.06 .26* .20* .13 .39** 1.00
19 Bowel function -.08 .12 .22* .26* .03 -.17 -.17 .11 -.19 -.07 -.18 -.15 -.22* -.19 -.20 -.19 -.18 -.24* 1.00
20 Cancer-related
ambiguity
.01 -.08 -.15 -.27** .07 .20* .02 -.17 -.07 .01 .06 .28** .29** .47** .43** .44** .40** .37** -.40** 1.00
21 Intrusive
thoughts
-.27** -.07 .09 .00 .14 -.05 -.19 -.04 -.09 .09 .03 .08 .58** .60** .65** .71** .26** .10 .00 .39** 1.00
22 Social activities -.13 .13 .05 .23* -.12 -.05 -.08 .01 -.04 -.08 -.25* -.08 -.10 -.11 -.14 -.11 -.13 -.22* .11 -.22* -.09 1.00
23 Intolerance of
uncertainty
-.16 -.20* .05 -.17 -.08 -.11 -.01 -.18 -.01 .15 .05 -.06 .53** .39** .48** .57** .02 -.08 -.18 .26** .55** -.12 1.00
24 Social support -.02 .26** -.01 .20 .00 .03 -.03 .11 .03 -.03 .13 -.01 -.23* -.33** -.26* -.26* -.07 .02 .04 -.18 -.07 .21* -.23* 1.00
25 Social
interference
.04 -.01 .10 -.10 .16 -.02 .37 .10 .01 .11 .03 -.05 .17 .37** .37** .43** .41** .16 -.29** .40** .30** -.27** .14 -.08
* Correlation is significant at the 0.05 level

** Correlation is significant at the 0.01 level

87

Table 14
Comparison of hypothesized and trimmed PLS models

Variable Model R
2
F p (df) Change
R2
Fdiff p-
value
Distress
1 .71 (9, 92)
2 .70 (6, 95)
1 Vs. 2 .01 .29 .83

88
Table 15
Direct and indirect associations
Direct Associations Indirect Associations

Emotional
distress
( β , p -value)
Ambiguity
( β , p -value)
Intrusive
thoughts
( β , p -value)
Social
activities
( β , p -value)
Emotional distress
Via
intrusive
thoughts
( β , p -value)
Via
ambiguity
and then
intrusive
thoughts
( β , p -value)
Medical Variables
Months since
diagnosis
-0.11, 0.02 0.10, 0.18 -0.07, 0.18
Surgery 0.12, 0.03 -0.03, 0.34 -0.02, 0.41
Physical symptoms 0.22, 0.005 0.53, 0.001 0.007, 0.47 -0.15, 0.03 0.05, 0.02

Dispositional
Characteristics

Neuroticism 0.26, 0.001 0.33, 0.001 0.04, 0.31 0.14, 0.006
Intolerance of
uncertainty
0.09, 0.14 0.24, 0.002 0.33, < 0.001 -0.16, 0.05 0.14, 0.003 0.02, 0.04
Psychosocial
Variables

Ambiguity 0.10, 0.13 0.21, 0.004 -0.11, 0.08 0.09, 0.01
Intrusive thoughts 0.44, < 0.001
Social activities 0.02, 0.41
Social interference 0.14, 0.03
Social support -0.13, 0.04
Interactions
Intolerance of
uncertainty *
Ambiguity
0.04, 0.28 -0.07, 0.18 0.20, 0.02
Social interference *
Social activities
-0.04, 0.27
Social support *
Social activities
0.13, 0.04
89

Figure 2. Full hypothesized structural model
Ambig u i t y
Int oler an c e
of

Uncerta i nty
Intrus i v e
T h oug h t s
Soci a l

A c t i v i t i es
Em oti on al
D i str es s
Neu r ot i c i sm
Su r gery
R adi a t i on
M on t h s
S i nce
D i agnos i s
P h y s i c al
S ymp t om s
(- )
(- )
(- )
(- )
(- )
(- )
(- )
(- )
(- )
(- )
(+)
(+ )
(+ )
(+ )
(+ )
(+ )
(+ )
(+ )
(+)
(+ )
(+)
(+ )
(+ )
(+ )
(+)
90

Figure 3. Trimmed structural model
Am big u ity
Int ole r ance

of

Uncertai nty
Intr u si v e

Though ts
So cia l

A cti vities
E mo tio nal

Distr es s
N eur ot ici sm
Sur gery
Mont h s
Si nce

Diagno sis
P h y sical

S ympt om s
(- )
(- )
(- )
(- )
(+ )
(+ )
(+ )
(+ )
(+ )
(+ )
(+ )
(+ )
(+ )
(+)
91

-1.2
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
-2 -1.5 -1 -0.5 0 0.5 1 1.5 2
Mean-centered Social Activities
Mean-centered Ambiguity
Low IUS
High IUS

Figure 4. Interaction between intolerance of uncertainty and cancer-related ambiguity in
association with social activities
92

Figure 5. Interaction between social support and social activities in association with emotional
distress

-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
-2 -1.5 -1 -0.5 0 0.5 1 1.5 2
Mean centered Emotional Distress
Mean-centered Social Activities
Low SS
High SS
93
Appendix 1: Results for Full Hypothesized Model

94
Appendix 2: Questionnaire Packet
Date: / / ID:_____________

P ATIE NT’S MEDICA L INF ORM ATIO N

1. Primary cancer site
[ ] colon
[ ] rectum

2. Date of first diagnosis with metastatic disease: ____(mo.)/ ____(day) / ________(yr.)

3. Current treatment (check all that apply):
[ ] chemotherapy (please specify type):______________________________________
[ ] radiation
[ ] other (please specify type): _____________________________________________

4. Past treatment (check all that apply):
[ ] chemotherapy:______________________________________
[ ] radiation
[ ] surgery
[ ] other (please specify type): _____________________________________________

5. Stoma status (check one):
[ ] Current, reversible
[ ] Current, permanent
[ ] Past, reversed
[ ] None

6. Most recent tumor response (check one):
[ ] Complete response
[ ] Partial response
[ ] Stable disease
[ ] Progressive disease

95
Toda y ’ s Da te: _____/_____/________ ID: ________________

Demographic Information

Please fill out the following information to the best of your knowledge.

1. Age: _______ years old

2. Gender: [ ] Female [ ] Male

3. What is your marital status?
[ ] Single/Separated/Divorced/Widowed [ ] Married/Partnered

4. Please check the highest level of education you have completed. (check one)
[ ] Grade school (1-8 yrs) [ ] Associate Degree earned (AA or AD)
[ ] Some high school (9-11 yrs) [ ] Bachelors Degree earned (BA or BS)
[ ] High School Graduate or GED [ ] Masters Degree earned (MA, MS,
MBA, MSW, etc.)
[ ] Vocational or training school after
high school graduation
[ ] Doctoral Degree earned (MD, PhD,
JD, etc.)

5. Please check one income range that best describes your fa mi l y ’s tot a l in c ome be for e tax e s for the previous year, including salaries, wages, tips, social security, and any other income.
[ ] Under $20,000 [ ] $110,001 - $140,000
[ ] $20,001 - $50,000 [ ] $140,001- $170,000
[ ] $50,001 - $80,000 [ ] $170,001-$200,000
[ ] $80,001 - $110,000 [ ] Over $200,000

6. Check the box that most closely represents your ethnic identification?
[ ] Black (African) American, NOT Hispanic [ ] Asian/Asian American
[ ] White, Hispanic [ ] Native American
[ ] Black, Hispanic
[ ] Mixed race, Hispanic
[ ] White (Anglo/Caucasian/European),
NOT Hispanic
[ ] Caribbean Islander (NOT Hispanic) [ ] Other (specify) __________

96

CES-D (Depression): Circle the number of each statement that best describes how often you felt
or behaved during the past month.

During t he pa s t m o nth…
Rarely or
none of the
time
Some or a
little of the
time
Occasionally or
a moderate
amount of the
time
Most or all
of the time
1. I wa s bother e d b y thi n gs that usuall y don’t bother me
0 1 2 3
2. I did not feel like eating; my appetite was
poor
0 1 2 3
3. I felt that I could not shake off the blues
even with help from my family and friends
0 1 2 3
4. I felt that I was just as good as other people 0 1 2 3
5. I had trouble keeping my mind on what I
was doing
0 1 2 3
6. I felt depressed

0 1 2 3
7. I felt that everything I did was an effort

0 1 2 3
8. I felt hopeful about the future

0 1 2 3
9. I thought my life had been a failure

0 1 2 3
10. I felt fearful

0 1 2 3
11. My sleep was restless

0 1 2 3
12. I was happy

0 1 2 3
13. I talked less than usual

0 1 2 3
14. I felt lonely

0 1 2 3
15. People were unfriendly

0 1 2 3
16. I enjoyed life

0 1 2 3
17. I had crying spells

0 1 2 3
18. I felt sad

0 1 2 3
19. I felt that people disliked me

0 1 2 3
20. I c ould not ge t “ g oin g ” 0 1 2 3
21.
HADS-Anxiety:
97
Please read each group of statements carefully, and then pick out the one statement in each group
that best describes the way you have been feeling during the past month. Circle the number
beside the statement you picked. Be sure to read all the statements in each group before making
your choice.

1) I feel tense or "wound up."
0. Most of the time
1. A lot of the time
2. From time to time, occasionally
3. Not at all

2) I get a sort of frightened feeling as if
something awful is about to happen.
0. Very definitely and quite badly
1. Yes, but not too badly
2. A little, but it doesn't worry me
3. Not at all

3) Worrying thoughts go through my
mind.
0. A great deal of the time
1. A lot of the time
2. From time to time but not too often
3. Only occasionally

4) I can sit at ease and feel relaxed.
0. Definitely
1. Usually
2. Not often
3. Not at all

5) I get a sort of frightened feeling like
"butterflies" in the stomach.
0. Not at all
1. Occasionally
2. Quite often
3. Very often

6) I feel restless as if I have to be on the
98
move.
0. Very much indeed
1. Quite a lot
2. Not very much
3. Not at all

7) I get sudden feelings of panic.
0. Very often indeed
1. Quite often
2. Not very often
3. Not at all

PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

99
Intolerance of Uncertainty (IUS): You will find below a series of statements, which describe
how people may react to the uncertainties of life. Please use the scale below to describe to what
extent each item is characteristic of you. Please circle a number (1 to 5) that describes you best.

Not at all
characteris
tic of me
Somewhat
characteris
tic of me
Entirely
characteris
tic of me
1. Unforseen events
upset me greatly.
1 2 3 4 5
2. It frustrates me not
having all the
information I need.
1 2 3 4 5
3. Uncertainty keeps
me from living a full
life.
1 2 3 4 5
4. One should always
look ahead so as to
avoid surprises.
1 2 3 4 5
5. A small unforeseen
event can spoil
everything, even with
the best of planning
1 2 3 4 5
6 .
Wh en
it ’s
time
t o

act, uncertainty
paralyses me.
1 2 3 4 5
7. When I am
uncer ta in
I
can ’t

function very well.
1 2 3 4 5
8. I always want to
know what the future
has in store for me.
1 2 3 4 5
9 .
I
can ’t
sta nd
b ei ng

taken by surprise.
1 2 3 4 5
PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

100
10. I should be able
to organize
everything in
advance.
1 2 3 4 5
11. The smallest
doubt can stop me
from acting.
1 2 3 4 5
12. I must get away
from all uncertain
situations.
1 2 3 4 5

PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

101
IES-R (Intrusive Thoughts):
Below is a list of difficulties people sometimes have after stressful life events. Please read each
item, and then indicate how bothersome each difficulty has been for you during the past month
with respect to your colorectal cancer.

Not at all
A little bit
Moderately
Quite a bit
Extremely
1. Any reminder brought back feelings about it.
0 1 2 3 4
2. I had trouble staying asleep.
0 1 2 3 4
3. Other things kept making me think about it.
0 1 2 3 4
4. I thou g ht about it whe n I didn’t m e a n to.
0 1 2 3 4
5. Pictures about it popped into my mind.
0 1 2 3 4
6. I found myself acting or feeling like I was
back at that time.
0 1 2 3 4
7. I had waves of strong feelings about it.
0 1 2 3 4
8. I had dreams about it.
0 1 2 3 4
PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

102
Social Activities (SAL): This list contains a diversity of activities that people sometimes enjoy.
Please rate the frequency that you have done each activity in the past month.

Frequency

Never
1-3 times per month
1-2 times per week
3-6 times per week
Daily
1. Shopping with ot he rs who don’ t l ive w it h y ou 0 1 2 3 4
2. Seeing a movie in the theater with a friend, family
member, or acquaintance
0 1 2 3 4
3. Going to a sports game to watch with others 0 1 2 3 4
4. Attending a concert, theater, or other cultural or
musical event with a friend, family member, or
acquaintance
0 1 2 3 4
5. Attending a party or social gathering 0 1 2 3 4
6. Eating a meal at a restaurant with others 0 1 2 3 4
7. Visiting the homes of my friends or acquaintances 0 1 2 3 4

PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

103
MSKCC-Bowel Functioning Index:
Please tell us about your experiences with bowel-related symptoms
Over t h e last 4 w e e k s…
Always
Most of
the time
Some-
times
Rarely
Never
1. Do you feel like you have totally emptied your bowels after a
bowel movement?
1 2 3 4 5
2. Do you get to the toilet on time? 1 2 3 4 5
3. Do you have another bowel movement within 15 minutes of
your last bowel movement?
1 2 3 4 5
4. Do you know the difference between having to pass gas and
needing to have a bowel movement?
1 2 3 4 5
5. Have you used medicines to decrease the number of bowel
movements (e.g. Imodium, Lomotil)
1 2 3 4 5
6. Have you had diarrhea (no form, watery stool)? 1 2 3 4 5
7. Have you had loose stool (slight form, but mushy)? 1 2 3 4 5
8. Have you been able to wait 15 minutes to get to the toilet
when you feel like you are going to have a bowel movement?
1 2 3 4 5
9. Have you been able to control the passage of gas (air)? 1 2 3 4 5
10. Have you limited the types of solid food you eat to control
your bowel movements?
1 2 3 4 5
11. Have you limited the types of liquids you drink to control
your bowel movements?
1 2 3 4 5
12. Have you had soilage (leakage of stool) of your
undergarments during the day?
1 2 3 4 5
13. Have you used a tissue, napkin, and/or pad in your
undergarments during the day in case of stool leakage?
1 2 3 4 5
14. Have you had soilage (leakage of stool) of your
undergarments when you go to bed?
1 2 3 4 5
15. Have you had to alter your activities because of your bowel
function?
1 2 3 4 5
ADDITIONAL ITEMS FOR DESCRIPTION
16. Have you been able to predict when you would have a bowel
movement (e.g. after eating)?
1 2 3 4 5
17. Have you been able to do things to control your bowel
movements (e.g. diet, medication)?
1 2 3 4 5
18. Have you felt embarrassed about your bowel symptoms? 1 2 3 4 5

PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

104
Mishel Uncertainty in Illness Scale:
Please read each statement. Then circle the number under the column that most closely measures
how you are feeling during the past month.

In t h e p ast m on th…
Strongly
Disagree
Disagree Undecided Agree Strongly
Agree
1. I am unsure if my illness is getting better
or worse.
1 2 3 4 5
2. It is unclear how bad my pain will be.

1 2 3 4 5
3. I do not know when to expect things will
be done to me.
1 2 3 4 5
4. My symptoms continue to change
unpredictably.
1 2 3 4 5
5. My treatment is too complex to figure out. 1 2 3 4 5
6. It is difficult to know if the treatments or
medications I am getting are helping.
1 2 3 4 5
7. Because of the unpredictability of my
illness, I cannot plan for the future.
1 2 3 4 5
8. The course of my illness keeps changing.
I have good and bad days.
1 2 3 4 5
9. I t’s v a g ue to m e how I will mana ge m y care.
1 2 3 4 5
10. It is not clear what is going to happen to
me.
1 2 3 4 5
11. The effectiveness of the treatment is
undetermined.
1 2 3 4 5
12. It is difficult to determine how long it will
be before I can care for myself.
1 2 3 4 5
13. Because of the treatment, what I can do
and cannot do keeps changing.
1 2 3 4 5

PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

105
EORTC QLQ-C30:
We are interested in some things about you and your health during the past month. Please
answer all of the questions yourself by circling the number that best applies to you.

Not
at all

A
little

Quite
a bit

Very
Much
1. Did you have any trouble doing strenuous activities like
carrying a heavy shopping bag or a suitcase?
1 2 3 4
2. Did you have any trouble taking a long walk?

1 2 3 4
3. Did you have any trouble taking a short walk outside of the
house?
1 2 3 4
4. Did you need to stay in bed or a chair during the day?

1 2 3 4
5. Did you need help with eating, dressing, washing yourself or
using the toilet?
1 2 3 4
6. Were you limited in doing either your work or other daily
activities?
1 2 3 4
7. Were you limited in pursuing your hobbies or other leisure
time activities?
1 2 3 4
8. Were you short of breath?

1 2 3 4
9. (P) Have you had pain?

1 2 3 4
10. (F) Did you need to rest?

1 2 3 4
11. Have you had trouble sleeping?

1 2 3 4
12. (F) Have you felt weak?

1 2 3 4
13. Have you lacked appetite?

1 2 3 4
14. Have you felt nauseated?

1 2 3 4
15. Have you vomited?

1 2 3 4
16. Have you been constipated?

1 2 3 4
17. Have you had diarrhea?

1 2 3 4
18. (F) Were you tired?

1 2 3 4
19. (P) Did pain interfere with your daily activities?

1 2 3 4
Not A Quite Very
PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

106
at all little a bit Much
20. Did you have difficulty in concentrating on things, like
reading a newspaper or watching television?
1 2 3 4
21. (EF) Did you feel tense?

1 2 3 4
22. (EF) Did you worry?

1 2 3 4
23. (EF) Did you feel irritable?

1 2 3 4
24. (EF) Did you feel depressed?

1 2 3 4
25. Have you had difficulty remembering things?

1 2 3 4
26. (SF) Has your physical condition or medical treatment
interfered with your family life?
1 2 3 4
27. (SF) Has your physical condition or medical treatment
interfered with your social activities?
1 2 3 4
28. Has your physical condition or medical treatment caused you
financial difficulties?
1 2 3 4
29. How would you rate your overall health during the past
month?
1 2 3 4
30. How would you rate your overall quality of life during the
past month?
1 2 3 4

(P) Pain
(F) Fatigue
(EF) Emotional Dysfunction
(SF) Social Functioning

PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

107
Neuroticism (EPQR-N): Are the following statements characteristic of you?
1. Does your mood often go up and down?

Yes No
2. Do y ou e ve r fe e l ‘just m iser a ble’ f o r no r e a son?

Yes No
3. Do y ou o fte n fe e l ‘f e d - up’?

Yes No
4. Would you call yourself a nervous person?

Yes No
5. Are you a worrier?

Yes No
6. W ould y ou c a ll y ourse lf ten se or ‘ hi g hl y strun g ’ ?

Yes No
7. Do you worry too long after an embarrassing experience?

Yes No
8. Do y ou suf fe r fr om ‘n e rve s’?

Yes No
9. Do you often feel lonely?

Yes No
10. Are you often troubled about feelings of guilt?

Yes No
11. Are you an irritable person?

Yes No
12. Are your feelings easily hurt?

Yes No

PSYCHOSOCIAL ADJUSTMENT METASTATIC COLORECTAL CANCER

108
MOS-Social Support: People sometimes look to others for companionship, assistance, or other
types of support.

1. About how many close friends and close relatives do
you have (people who you feel at ease with and can
talk to about what is on your mind)? Please write in
the number of close friends and close relatives that
you have.

__________

How often in the past month has each of the
following kinds of support been available to you if
you need it?
None
of the
time
A
little
of
the
time
Some
of the
time
Most
of the
time
All
of
the
time
2. Someone to help you if you were confined to bed 1 2 3 4 5
3. Someone you can count on to listen to you when you
need to talk
1 2 3 4 5
4. Someone to give you good advice about a crisis 1 2 3 4 5
5. Someone to take you to the doctor if you need it 1 2 3 4 5
6. Someone who shows you love and affection 1 2 3 4 5
7. Someone to have a good time with 1 2 3 4 5
8. Someone to give you information to help you
understand a situation
1 2 3 4 5
9. Someone to confide in or talk to about yourself or
your problems
1 2 3 4 5
10. Someone who hugs you 1 2 3 4 5
11. Someone to get together with for relaxation 1 2 3 4 5
12. Someone to prepare your meals if you were unable to
do it yourself
1 2 3 4 5
13. Someone whose advice you really want 1 2 3 4 5
14. Someone to do things with to help you get your mind
off things
1 2 3 4 5
15. Someone to help with daily chores if you were sick 1 2 3 4 5
16. Someone to share your most private worries and fears
with
1 2 3 4 5
17. Someone to turn to for suggestions about how to deal
with a personal problem
1 2 3 4 5
18. Someone to do something enjoyable with 1 2 3 4 5
19. Someone who understands your problems 1 2 3 4 5
20. Someone to love and make you feel wanted 1 2 3 4 5

Abstract (if available)

Abstract Objective: Patients with metastatic colorectal cancer (mCRC) may experience greater emotional distress than patients with less advanced disease, but few studies have explored the aspects of the mCRC experience that are related to poorer emotional functioning. The purpose of this study was to test a model that identifies possible cancer‐related and psychosocial correlates of emotional distress in patients with mCRC. Methods: This cross‐sectional, questionnaire‐based study included 102 patients participating in active treatment for mCRC. Partial least squares (PLS) modeling analyses tested the key hypotheses, adjusting for months since diagnosis, cancer surgery, and neuroticism. Results: In general, patients reported moderate emotional distress. Greater physical symptoms and cancer-related ambiguity were directly associated with emotional distress. Greater physical symptoms, cancer‐related ambiguity, and intolerance of uncertainty were associated with greater emotional distress indirectly, via their relations with greater intrusive thoughts. Patients who experienced more physical symptoms also participated in fewer social activities, but fewer social activities were only associated with distress in patients low in social support. Conclusion: Patients with mCRC who report greater physical symptoms, perceive their cancer experience as highly ambiguous, or view uncertainty as threatening may be at elevated risk for emotional distress. Incomplete cognitive processing of the cancer experience, marked by greater intrusive thoughts, may partially account for these relations.

Linked assets

University of Southern California Dissertations and Theses

Conceptually similar

PDF

Mindfulness among patients with advanced colorectal cancer

PDF

Psychosexual adjustment among low-income Latinas with cervical cancer

PDF

Psychosocial adjustment of Latina cervical cancer patients

PDF

The influences of anxiety, coping, and social support on physical functioning among heart failure patients

PDF

Social support, constraints, and protective buffering in prostate cancer patients and their partners

PDF

Role of age and comorbidities in the quality of life of newly diagnosed prostate cancer patients

PDF

Health-related quality of life correlates of the treatment decision making process of newly diagnosed prostate cancer patients

PDF

Discussion during treatment decision-making predicts emotional adjustment in prostate cancer patients

PDF

Partners of breast cancer survivors: Research participation and understanding of survivors' concerns

PDF

The effects of health-related spousal influence on couples coping with chronic heart failure: an application of the actor-partner interdependence model

PDF

Investigating racial and ethnic disparities in patient experiences with care and health services use following colorectal cancer diagnosis among older adults with comorbid chronic conditions

PDF

The effects of physical functioning and public stigma on psychological distress as mediated by cognitive and social factors among Korean survivors of childhood cancer

PDF

Dedifferentiation of emotion regulation strategies in the aging brain: an MVPA investigation

PDF

Racial/ethnic differences in colorectal cancer patient experiences, health care utilization and their association with mortality: findings from the SEER-CAHPS data

PDF

Sources of stability and change in the trajectory of openness to experience across the lifespan

PDF

Examining the associations of respiratory problems with psychological functioning and the moderating role of engagement in pleasurable activities during late adolescence

PDF

Childhood cancer survivorship: parental factors associated with survivor's follow-up care behavior and mental health

PDF

The effect of renal function on toxicity of E7389 (eribulin) among patients with bladder cancer

PDF

Eribulin in advanced bladder cancer patients: a phase I/II clinical trial

PDF

A theory-informed approach to understanding family correlates of treatment use among Latinxs with psychotic symptoms

Asset Metadata

Creator Eisenberg, Stacy Ann (author)

Core Title Psychosocial adjustment among patients with metastatic colorectal cancer

School College of Letters, Arts and Sciences

Degree Doctor of Philosophy

Degree Program Psychology

Publication Date 07/08/2014

Defense Date 05/23/2014

Publisher University of Southern California (original), University of Southern California. Libraries (digital)

Tag anxiety,colorectal cancer,Depression,intrusive thoughts,metastatic cancer,OAI-PMH Harvest,social activities,uncertainty

Format application/pdf (imt)

Language English

Contributor Electronically uploaded by the author (provenance)

Advisor Meyerowitz, Beth E. (committee chair), Clarke, Peter (committee member), Gatz, Margaret (committee member), John, Richard S. (committee member), Knight, Bob G. (committee member)

Creator Email stacyeisenberg@gmail.com

Permanent Link (DOI) https://doi.org/10.25549/usctheses-c3-433296

Unique identifier UC11286883

Identifier etd-EisenbergS-2634.pdf (filename),usctheses-c3-433296 (legacy record id)

Legacy Identifier etd-EisenbergS-2634.pdf

Dmrecord 433296

Document Type Dissertation

Format application/pdf (imt)

Rights Eisenberg, Stacy Ann

Type texts

Source University of Southern California (contributing entity), University of Southern California Dissertations and Theses (collection)

Access Conditions The author retains rights to his/her dissertation, thesis or other graduate work according to U.S. copyright law. Electronic access is being provided by the USC Libraries in agreement with the a...

Repository Name University of Southern California Digital Library

Repository Location USC Digital Library, University of Southern California, University Park Campus MC 2810, 3434 South Grand Avenue, 2nd Floor, Los Angeles, California 90089-2810, USA