Evaluating the World Health Organization’s International Classification of Functioning,Disability and Health Framework as a Participation Model for Cancer Survivors in Turkey

Abstract

Improvements in diagnosis and treatment options for cancer now allow cancer survivors to live longer, and as a result, services are necessary to help individuals live an active and meaningful life in the community. The purpose of this study was to evaluate the World Health Organization’s International Classification of Functioning, Disability and Health (ICF) framework as a participation model for cancer survivors in Turkey. Results from simultaneous regression analyses indicated educational attainment, fatigue, perceived stress, role functioning, social functioning, core self-evaluations, independent self-construal, social support, and autonomy support were significantly associated with participation. Specific interventions including health education, psychological workshops, support groups, and assistive technology may improve cancer survivors’ motivation and desire to actively engage in community activities. Higher levels of participation were also found when cancer survivors were involved in the treatment decision-making process, and felt cared for and understood by their treatment providers.

Keywords

cancer rehabilitation counseling ICF participation

Participation in life situations has numerous positive effects on individuals with chronic illness and disability. Increased participation is associated with improved physical and psychological health, quality of life (J. Chan, Chan, Ditchman, Phillips, & Chou, 2013; Lindahl-Jacobsen, Hansen, la Cour, & Søndergaard, 2014; Meulenkamp, Cardol, van der Hoek, Francke, & Rijken, 2013), and life satisfaction for people with chronic illnesses and disabilities, including people with cancer (Bergström, von Koch, Andersson, Tham, & Eriksson, 2015; J. Chan et al., 2013; Lund & Lexell, 2009; Nikolić, Ilić-Stošović, Kolarević, Djurdjević, Ilić, & Djuričić, 2015). It is noteworthy that improvements in physical, psychological, and social health and well-being may increase survival rate, life expectancy and reduce health care costs associated with chronic illness and disability (F. Chan, Tarvydas, Blalock, Strauser, & Atkins, 2009).

Despite the benefits of engaging individuals in various aspects of society, participation levels of cancer survivors are significantly lower when compared with people without cancer. Research indicates cancer survivors with cancer history of less than 5 years or with cancer history of 5 years or more since diagnosis have significantly higher performance limitations and participation restrictions in performing household chores, attending social events and outdoor events (e.g., shopping or seeing a movie), and attending sporting events than people with no cancer history (Ness, Wall, Oakes, Robison, & Gurney, 2006).

To fully understand the barriers to participation, the International Classification of Functioning, Disability and Health (ICF) model may facilitate conceptualization of how cancer-related impairments manifest in activity limitations (e.g., grooming, dressing, and child care) and restrict participation (e.g., attending community activities and reduced job expectations) for cancer survivors (Gilchrist et al., 2009). According to ICF, it is the personal and environmental factors and their interactions (P × E) that determine level of functioning and participation, not simply impairments. For example, two people with the same disability may have different levels of participation outcomes due to the mediation effects of contextual factors (i.e., personal and environmental factors) between body functioning/activities and participation.

A comprehensive review of the literature of the ICF model indicated demographic variables (e.g., age, gender, education level, income level), impairment-related factors (e.g., treatment type and number of treatments, secondary health conditions, years since diagnosis, perceived stress, pain, fatigue and sleep disturbance), personal factors (e.g., core self-evaluation, resilience, spirituality, religiosity and meaning in life, individualistic versus collectivistic self-construal), and environmental factors (e.g., perceived social stigma, social support, and health care climate) may influence participation of cancer survivors (Bleyer & Barr, 2007; Deimling, Bowman, & Wagner, 2007; Goker, Guvenal, Yanikkerem, Turhan, & Koyuncu, 2011; Hewitt, Rowland, & Yancik, 2003; Kreitler, Peleg, & Ehrenfeld, 2007; Livneh, Chan, & Kaya, 2014; Nazik, Nazik, Ozdemir, & Soydan, 2014; Ness et al., 2006; Roscoe et al., 2007; Smith, Nolan, Robison, Hudson, & Ness, 2011; Toptas et al., 2014) For example, age has been associated with decreased functioning and increased participation restrictions for cancer survivors (Deimling et al., 2007). In addition, gender was significantly associated with participation restrictions, with females having greater participation restrictions (Deimling et al., 2007; Ness et al., 2006). Findings regarding the relationship between education level and functional limitations and participation restrictions are mixed (Belanger, Plotnikoff, Clark, & Courneya, 2013; Citak & Tulek, 2013), but research does indicate cancer survivors with higher levels of income have better physical and cognitive functioning than those with lower incomes (Goker et al., 2011)

Impairment-related factors negatively influenced participation of cancer survivors (Deimling et al., 2007). Cancer survivors in later stages of cancer who had comorbid conditions and received more than one type of treatment (e.g., surgery, chemotherapy, and radiotherapy) had lower levels of participation (Deimling et al., 2007; Hewitt et al., 2003; Ness et al., 2005). Furthermore, cancer treatments are believed to cause short- and long-term, health-related physical, intellectual, and emotional problems, leading to lower levels of functioning and participation (Burris & Andrykowski, 2011; Ness et al., 2005; van der Mei, Dijkers, & Heerkens, 2011). Conversely, cancer survivors who had a higher levels of positive psychological characteristics, including core self-evaluation, resilience, and meaning in life, were more likely to have a higher level of participation (Costanzo, Ryff, & Singer, 2009; Rippentrop, Altmaier, & Burns, 2006; Rowland & Baker, 2005; Smedema, Chan, & Phillips, 2014; Wenzel et al., 2002). Cancer survivors in supportive environments, including higher levels of social support, less perceived stigma, and nurturing health care climates, were also more likely to have higher levels of participation (Afsaroglu, Okutur, & Demir, 2010; Baard, Deci, & Ryan, 2005; Helgeson & Cohen, 1996; Nausheen, Gidron, Peveler, & Moss-Morris, 2009).

The literature review indicates that demographic variables, impairment-related variables, personal and environmental factors are significantly associated with functioning and participation of cancer survivors. However, most of the studies included in the literature explained univariate relationships between those variables and participation. Moreover, these studies did not utilize comprehensive theoretical models to explain functioning and participation. Therefore, there is a need to investigate simultaneous effect of demographic variables, impairment-related variables, personal and environmental factors on participation using a more comprehensive theoretical model such as ICF.

Study Purpose

Despite the benefits on overall health and functioning associated with participation, few studies have comprehensively evaluated the ICF as a participation model for cancer survivors. A broad investigation can inform the design and validation of ICF-based psychosocial interventions for cancer survivors. Consequently, the purpose of this study was to investigate the relationship between ICF components (i.e., impairment-related factors, personal and environmental factors, and activity/functioning variables) and participation for cancer survivors.

Method

Participants and Procedures

The sample in this study consisted of 192 cancer survivors recruited from a major cancer institute and a nonprofit organization in Turkey as part of an ICF project sponsored by the Rehabilitation Research and Training Center on Evidence-Based Practice in Vocational Rehabilitation (RRTC-EBP-VR). To recruit participants, collaborators reached out to cancer survivors individually or via social media, informed them about the study, and provided instructions for participation. Individuals who volunteered to participate in the study completed a survey packet using a secure online survey tool. Survey packet included a consent form explaining the nature of the study and the potential risks and benefits of participating in the study before the questionnaires section of the study. The consent form explained that participating in this study was voluntary and that not participating in the study would not have any negative consequences.

A total of 533 cancer survivors attempted to complete the survey online; however, only 192 completed it. The participants had to be between 18 years and 65 years of age, diagnosed with cancer, have a self-reported sixth-grade reading level or above, and be a citizen of Turkey to participate in this study. Participants who were not diagnosed with cancer or were diagnosed with any other disability were not included in the sample. Sample and disability-related characteristics of participants are shown in Table 1.

Table 1.

Demographic- and Impairment-Related Characteristics of Participants.

Demographic- and Impairment-Related Characteristics	n (%)	M (SD)
Demographic covariates
Age		45.82 (11.46)
Gender
Men	33 (17.2)
Women	159 (82.8)
Marital status
Married	124 (64.6)
Not married	68 (35.4)
Education
<High school	43 (22.4)
High school graduate	41 (21.4)
Postsecondary education/associate’s degree	29 (15.1)
Bachelor’s degree	52 (27.1)
Master’s degree or above	27 (14.1)
Income level
Low	99 (51.6)
Medium	70 (36.5)
High	23 (11.9)
Disability-related variables
Type of cancer
Breast cancer	100 (52.1)
Other	92 (47.9)
Cancer stage
First stage	65 (33.9)
Second stage	49 (25.5)
Third stage	55 (28.6)
Fourth stage	23 (12.0)
Patient type
Inpatient	27 (14.1)
Outpatient	165 (85.9)
Type of treatment
Surgery	152 (79.2)
Chemotherapy	150 (78.1)
Radiotherapy	102 (53.1)
Number of treatments received
0	2 (1)
1	52 (27.1)
2	62 (32.3)
3	76 (39.6)
Secondary disabilities
Yes	92 (47.9)
No	94 (48.9)
Type of secondary disabilities
Anxiety disorders	22 (11.5)
Arthritis and rheumatism	22 (11.5)
Asthma and other allergies	18 (9.3)
Attention-deficit hyperactivity disorder	11 (5.7)
Blood disorders	11 (5.7)
Cardiac and other conditions of circulatory system	17 (8.8)
Depression and other mood disorders	37 (19.2)
Diabetes mellitus	14 (7.2)
Digestive	16 (8.3)
Eating disorders	14 (7.2)
End-stage renal disease and other genitourinary system	10 (5.2)
Onset time since diagnosis	Range = 1–64 months	27.16 (24.8)

Note. N = 192.

Measures

This study included demographic information form and several standardized measurement tools to assess independent and dependent variables. Although, most of the assessment tools used in this study are often used in rehabilitation and disability research, some of the assessment tools including Self-Construal Scale (SCS), purpose in life scale are less commonly used in the field. The total number of questions in the assessment tools was 167.

Outcome variable

The outcome variable for this study was participation. Participation was measured by the Impact on Participation and Autonomy Scale (IPA). The IPA was developed by Cardol, de Haan, van den Bos, de Jong, and de Groot (1999) to assess patients’ participation as defined by the World Health Organization’s (WHO) ICF model. The English version of the IPA was validated by Sibley et al. (2006), and internal consistency reliability estimates (Cronbach’s α) for the five subscales range from .86 to .91 (Kersten, 2007). Although, the IPA is comprised of five subscales, a total score was used in this study. The total score is calculated by summing scores on the five subscales. A Cronbach’s alpha of .95 was found for the composite scale with the sample in the present study.

Predictor variables

The predictor variables for this study were ICF constructs of demographic variables, impairment-related factors, personal and environmental factors, and activity/functioning variables.

Demographic variables

A demographic questionnaire was used to identify sociodemographic and cancer-related characteristics of the participants. The demographic questionnaire included items related to age, gender, educational attainment, income level, type of cancer, cancer stage, type of treatment(s), number of treatments, patient type, time since diagnosis, and secondary disabilities.

Impairment-related factors

Impairment-related variables included pain, fatigue, sleep disturbance, and perceived stress. Pain was measured by the two-item Pain Scale included in the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ). Participants were asked to rate whether they had pain and if pain interfered with daily life using a 4-point Likert-type scale ranging from 1 (not at all) to 4 (very much). The internal consistency reliability coefficient (Cronbach’s α) for the pain scale was .72 for cancer patients in Turkey (Cankurtaran et al., 2008). Fatigue was measured by the Brief Fatigue Inventory (BFI) developed by Mendoza et al. (1999). Individuals are asked to rate severity of their fatigue at its “worst,” “usual,” and “now,” ranging from 0 (no fatigue) to 10 (fatigue as bad as you can imagine). Previous research estimated internal consistency reliability (Cronbach’s α) coefficient at .96 (Mendoza et al., 1999). Sleep was measured by 12 items on the Medical Outcomes Study-Sleep Scale (MOS-Sleep) developed by Hays and Stewart (1992) to assess various sleep dimensions. Internal consistency reliability coefficients (Cronbach’s α) range from .71 to .81 for a sample of people with Type I and Type II diabetes with painful, distal, symmetrical, and sensorimotor polyneuropathy in Germany, Hungary, Poland, Australia, the United Kingdom, and South Africa (Viala-Danten, Martin, Guillemin, & Hays, 2008). Perceived stress was measured by a short version of the Perceived Stress Scale (PSS) developed by Cohen and Williamson (1988) to measure the extent to which life situations are appraised as stressful. Cronbach’s alpha level was estimated at .86 for newly diagnosed breast cancer patients (Cohen, Kamarck, & Mermelstein, 1983).

Personal factors

Personal factors included core self-evaluation, resilience, purpose in life, and self-construal. Core self-evaluation was measured by a 12-item Core Self-Evaluation Scale (CSES) developed by Judge, Bono, Erez, and Locke (2005), to briefly assess broad, integrative personality traits including self-esteem, generalized self-efficacy, neuroticism, and locus of control. The average internal consistency reliability coefficient (Cronbach’s α) was reported at .84 (Judge et al., 2005). Resilience was measured by Brief Resilience Scale (BRS) developed by Smith et al. (2008) to assess a person’s ability to bounce back or recover from stress. The authors reported good internal consistency with Cronbach’s alpha ranging from .80 to .91 for samples of people with disabilities and healthy controls. Purpose in life was measured by the three items using purpose in life subscale of the Psychological Well-Being Scale (PWBS) developed by Ryff and Keyes (1995). The internal consistency reliability coefficient (Cronabach’s α) was estimated between .25 and .32 (Ryff, Seeman, & Weinstein, 2017). The modest alpha coefficients are the result of the small number of indicators per scale (Ryff & Keyes, 1995). Individualistic versus collectivistic characteristics was measured by the SCS, which was developed by Singelis (1994) to measure independent (emphasis on separateness and individuality) and interdependent (emphasis on connectedness and relations) self-construal.

Environmental factors

Environmental factors included perceived social support, perceived stigma, and health care climate. The Multidimensional Scale of Perceived Social Support (MSPSS) developed by Zimet, Dahlem, Zimet, and Farley (1988) was used to measure social support from multiple sources: family, friends, and significant others. Internal consistency (Cronbach’s α) of the scale was reported at .92 (Başol, 2008). The Perceived Disability Stigma Scale (PDSS) developed by Chan and Fujikawa (2013) was used to assess perceived disability stigma. The Cronbach’s alpha for the sample in the present study was found to be .83. The Health Care Climate Questionnaire (HCCQ) developed by Williams, Grow, Freedman, Ryan, and Deci (1996) was used to measure patients’ perceptions of their health care provider’s support for autonomy. The internal consistency reliability estimate for the HCCQ was reported at .95.

Activity/functioning

The European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30) was developed to assess the health-related quality of life of cancer patients participating in international clinical trials. For the purpose of this study, the five functioning scales, the QLQ-C30 (i.e., physical, role, cognitive, emotional, social) were used to operationalize the construct of activity. The reported internal consistency reliability coefficients (Cronbach’s α) for the QLQ subscales ranged from .56 to .85 for a sample of cancer patients in Turkey (Cankurtaran et al., 2008). Similar levels of Cronbach’s alphas ranging from .66 to .90 were found for the sample in the present study.

Data Analysis

The Statistical Package for Social Sciences (SPSS) 20.0 was utilized to conduct statistical analysis in this study. Descriptive statistics, preliminary data screening, simultaneous regression analysis, and hierarchical regression analysis were used to examine the data. To determine the sample size, an a priori power analysis was conducted using the G*Power software. Using an alpha of .05, a statistical power of .80, and a medium effect size of f² = .15 (Cohen, 1988), a total number of 190 participants was needed for the regression analyses. In addition to that, missing data were analyzed to see if it was random, and the missing data were imputed using regression predictions.

Results

Descriptive Statistics

Descriptive statistics including measures of central tendency and variability for all variables were calculated. A thorough review of these statistics is provided in Table 2. It should be noted that the descriptive statistics results were based on the ratings of the scales and not normative data.

Table 2.

Descriptive Statistics of Participants and Used Measurement Tools.

Descriptive statistics	Measurements	Minimum–maximum	M (SD)
Participation level	IPA	1–5	3.15 (0.65)
Fatigue level	BFI	0–10	4.65 (2.55)
Sleep disturbance	MOS-Sleep Scale	0–100	37.48 (22.03)
Stress	PSS	0–4	2.90 (0.57)
Pain level	PS of EORTC QLQ	0–100	34.06 (28.50)
Physical functioning	EORTC QLQ-30	0–100	66.17 (22.65)
Emotional functioning	EORTC QLQ-30	0–100	62.50 (25.69)
Social functioning	EORTC QLQ-30	0–100	66.50 (27.28)
Role functioning	EORTC QLQ-30	0–100	75.71 (27.45)
Cognitive functioning	EORTC QLQ-30	0–100	73.60 (23.94)
Core self-evaluations	CORE	1–5	3.33 (0.55)
Resilience	BRS	1–5	3.34 (0.79)
Purpose in life	PIL	1–7	4.56 (1.07)
Interdependent self-construal	SCS	1–7	5.10 (1.33)
Independent self-construal	SCS	1–7	5.04 (1.48)
Perceived social support	MPSS	1–7	5.54 (1.33)
Perceived stigma	PDSS	1–5	2.39 (0.66)
Autonomy support	HCCQ	1–7	4.71 (1.65)

Note. N = 192; IPA = Impact on Participation and Autonomy Scale; BFI = Brief Fatigue Inventory; MOS-SS = Medical Outcomes Study-Sleep Scale; PSS = Perceived Stress Scale; EORTC QLQ-30 = European Organization for Research and Treatment of Cancer Quality of Life Questionnaire; CORE = Core Self-Evaluation Scale; BRS = Brief Resilience Scale; PIL = Purpose in Life Scale; SCS = Self-Construal Scale; MPSS = The Multidimensional Scale of Perceived Social Support; PDSS = Perceived Disability Stigma Scale; HCCQ = Health Care Climate Questionnaire.

Predictors of Participation

Five separate simultaneous regression analyses were conducted to determine the relationships between ICF components (i.e., demographic variables, impairment-related factors, personal and environmental factors, activity/functioning variables) and participation. The effect of the significant predictor variables recruited from the simultaneous regression analyses on participation was tested using a final regression analysis. The results of all regression analyses are shown in Tables 3 and 4. Also, a summary of the results was given at below.

Table 3.

Five Different Regression Models With Predictor Variables.

Variable	R ²	B	SE B	β
Demographic variables	.08
Age		0.00	0.00	.09
Gender		−0.10	0.12	−.06
Education level		0.08	0.03	.18*
Income level		0.13	0.07	.13
Impairment-related variables	.33
Type of cancer		0.00	0.10	.00
Cancer stage		−0.17	0.05	−.11
Number of treatments		0.09	0.09	.12
Surgery		0.11	0.17	.07
Chemotherapy		−0.08	0.15	.05
Patient type		−0.04	0.13	−.02
Onset time since diagnosis		0.00	0.00	.08
Secondary health problems		−0.01	0.09	.00
Perceived stress		−0.18	0.08	−.16*
Fatigue		−0.05	0.02	−.22**
Pain		−0.00	0.00	−.10
Sleep disturbance		−0.00	0.00	−.08
Activity-related variables	.31
Physical functioning		0.003	0.002	.11
Role functioning		0.006	0.002	.23*
Emotional functioning		0.001	0.002	.03
Cognitive functioning		0.002	0.002	.06
Social functioning		0.005	0.002	.22*
Personal factors	.13
Core self-evaluations		0.27	0.10	.23**
Resilience		0.06	0.07	.08
Religiosity		−0.05	0.03	−.10
Purpose in life		−0.00	0.04	.00
Independent self-construal		−0.07	0.03	−.16*
Interdependent self-construal		−0.01	0.04	−.03
Environmental factors	.14
Perceived social support		0.07	0.03	.14*
Perceived autonomy support		0.11	0.02	.27**
Perceived stigma		−0.12	0.07	−.12

Note. F(4, 181) = 4.15; F(12, 173) = 7.13; F(5, 180) = 16.35; F(6, 179) = 4.86; F(3, 182) = 10.38.

p < .05. **p < .01.

Table 4.

Final Regression Model With the Significant Variables as Predictors.

Variable	R ²	B	SE B	β
	.40**
Demographic variables
Education		0.06	0.02	.13*
Impairment-related variables
Fatigue		−0.05	0.01	−.19**
Perceived stress		−0.03	0.09	−.02
Personal factors
Core self-evaluations		0.01	0.08	.01
Independent self-construal		−0.02	0.02	−.06
Environmental factors
Perceived social support		0.05	0.03	.11
Autonomy support		0.05	0.02	.13*
Activity variables
Role functioning		0.00	0.00	.20**
Social functioning		0.00	0.00	.16

Note. F(9, 176) = 13.21.

p < .05. **p < .01.

Demographic variables

The results indicate demographic variables accounted for 8% of the variance in participation, R = .29, R² = .08, F(4, 181) = 4.15, p < .01. The examination of the standardized partial regression coefficients after controlling for the effect of other variables in the regression model revealed only education attainment (β = .18, t(186) = 2.23, p < .05) was significantly associated with participation. Cancer survivors who had higher education levels were more likely to have a higher level of participation. Although income was significantly associated with participation, this relationship was rendered nonsignificant after controlling for the effect of other demographic variables in the simultaneous regression. The effect of income was mediated mainly by educational attainment. Overall, the results indicated that only education level was significantly positively associated with participation.

Impairment-related variables

The impairment-related variables accounted for 33% of variance in participation, R = .57, R² = .33, F(12, 173) = 7.13, p < .01. The examination of the standardized partial regression coefficients after controlling for the other variables in the regression model revealed fatigue, β = −.22, t(186) = −2.79, p < .01, and perceived stress, β = −.16, t(186) = −2.15, p < .05, were significantly associated with participation. Cancer survivors who had lower levels of fatigue and perceived stress were more likely to have higher levels of participation. After controlling for the other variables, cancer type, cancer stage, types of treatment, number of treatments, secondary disability, pain, and sleep disturbance were no longer associated with participation. The functional impact of these variables was mediated by fatigue and perceived stress, and the direction of the relationships between the impairment-related variables and participation was as expected. Impairment-related variables had negative relationship with participation. Overall, the results indicated that fatigue and perceived stress were significantly negatively associated with participation.

Activity-related variables

The activity-related variables accounted for 31% of the variance in participation, R = .55, R² = .31, F(5, 180) = 16.35, p < .01. The examination of the standardized partial regression coefficients after controlling for the effect of other variables revealed role functioning,β = .23, t(186) = 2.60, p < .05, and social functioning variables,β = .22, t(186) = 2.26, p < .05, were significantly associated with participation. Cancer survivors who had higher levels of role and social functioning were more likely to have higher levels of participation. After controlling for the effect of other variables, physical, emotional, and cognitive functioning were no longer associated with participation. The effects of these variables were mediated by role and social functioning variables. Overall, the results indicated that role functioning and social functioning were significantly positively associated with participation

Personal factors

The personal factors accounted for 13% of the variance in participation, R = .37, R² = .13, F(6, 179) = 4.73, p < .01. After controlling for the effect of other variables, the examination of the standardized partial regression coefficients revealed core self-evaluations,β = .23, t(186) = 2.75, p < .01, and independent self-construal,β = −.16, t(186) = 2.00, p < .05, were significantly associated with participation. Cancer survivors who had higher levels of core self-evaluations and lower levels of individualistic self-construal were more likely to have higher participation levels. After controlling for the other variables, resilience and collectivistic self-construal were not significantly associated with participation. The functional impact of these variables was mediated by core self-evaluations and individualistic self-construal. Overall, the results indicated that only core self-evaluations and independent self-construal were significantly positively associated with participation.

Environmental factors

The environmental factors accounted for 14% of variance in participation, R = .38, R² = .14, F(3, 182) = 10.38, p < .01. The examination of the standardized partial regression coefficients after controlling for the effect of other variables revealed perceived social support,β = .14, t(186) = 2.00, p < .05; and autonomy support,β = −.27, t(186) = 3.93, p < .01, was significantly associated with participation. Cancer survivors who had higher levels of perceived social support and autonomy support were more likely to have a higher level of participation. After controlling for the other variables, perceived stigma was no longer significantly associated with participation. The effect of perceived stigma was mediated by perceived social support and autonomy support. Overall, the results indicated that only perceived social support and autonomy support were significantly positively associated with participation.

A final simultaneous regression analysis was conducted to determine the effect of all of the significant predictor variables (i.e., educational attainment, fatigue, perceived stress, role functioning, social functioning, core self-evaluation, independent self-construal, perceived social support and autonomy support) on participation. These variables accounted for 40% of the variance in participation, R = .63, R² = .40, F(9, 176) = 13.21, p < .01. After controlling for the effect of other variables, the examination of the standardized partial regression coefficients revealed educational attainment,β = .13, t(186) = 2.29, p < .05; fatigue,β = −.19, t(186) = 2.74, p < .01; role functioning,β = .20, t(186) = 2.49, p < .05; and autonomy support,β = .13, t(186) = 2.02, p < .05, were significantly associated with participation. Educational attainment, role functioning, and autonomy support were positively associated with participation, whereas fatigue was inversely associated with participation. Cancer survivors who had higher levels of education, role functioning, and autonomy support and lower levels of fatigue were more likely to have a higher level of participation. After controlling for the other variables, perceived stress, social functioning, core self-evaluations, independent self-construal, and perceived social support were no longer significantly associated with participation. The functional impact of these variables was mediated by education level, fatigue, role functioning, and autonomy support. Overall, the final simultaneous regression results indicated that after controlling for the other variables; educational attainment, fatigue, autonomy support, and role functioning were significantly associated with participation.

Discussion

When interpreting the study’s results, it is necessary to recognize that Turkey is a collectivist society where group coherence and looking out for each other is important. Family ties are strong, and family members are expected to strive for the well-being of their families (Chhokar, Brodbeck, & House, 2014). Despite the importance of interdependency between members of society, receiving help from outside of a close circle is not desirable (Terzioglu, 2008). Therefore, family members tend to support their close network, and individuals who are ill strive not to become a burden (Ozdogan et al., 2006). Cancer survivors who maintain the ability to perform role functioning activities (e.g., work) are more likely to participate in community activities. Otherwise, individuals with cancer may isolate themselves to avoid becoming a burden on their family members (Ozdogan et al., 2006).

Fatigue and perceived stress were significantly associated with participation. Cancer survivors in Turkey experience stress because continuity of their lives is unexpectedly interrupted. The need to overcome challenges to receive cancer treatment, assume a dependent role, and deal with financial and societal challenges related to cancer, which can affect self-esteem, has a significant impact on perceived stress (Terzioglu, 2008). These stressors might cause participation restrictions and negatively affect daily life (Brunet, Love, Ramphal, & Sabiston, 2014). Fatigue is another construct that has physical and psychological components (Page & Adler, 2008). Therefore, the effects of impairment-related factors (e.g., type of cancer, cancer stage, number of treatment and secondary health issues) may manifest as fatigue and thus affect participation. Previous research also indicates that cancer-related pain, sleep disturbance, and fatigue are related physical symptoms. Particularly, mediation analysis shows cancer-related pain and sleep disturbance have a direct effect on fatigue (Beck, Dudley, & Barsevick, 2005; Kim & Yi, 2014). Therefore, pain and sleep disturbance may indirectly affect participation by causing variations in levels of fatigue for Turkish cancer survivors. Overall, the results indicated physiological factors (i.e., fatigue) and psychological factors (i.e., perceived stress) significantly influence the participation of cancer survivors in Turkey, which is consistent with cancer research in Western countries (Deimling et al., 2007; Kurtz, Kurtz, Stommel, Given, & Given, 2001).

The effect of educational attainment on participation may be a function of being more knowledgeable about health issues with access to an increased supportive social environment (Goker et al., 2011). It is also possible that cancer survivors with higher educational attainment perceive cancer as a treatable disease, are equipped with better coping skills, and are more motivated to normalize their cancer experience, whereas cancer survivors without a history of advanced education are more likely to play the “sick role” and see cancer as a direct path to death (Hirschman, 2001; Larsen, 2009).

Role and social functioning variables also significantly associated with participation. As Turkey is a collectivistic society, the ability to perform family life, social roles, and daily activities may be a more important influence on participation for Turkish cancer survivors (Chhokar et al., 2014; Terzioglu, 2008). Performing role and social functioning activities might help cancer survivors feel valued, contribute to their close social network, and attend more life activities (Terzioglu, 2008).

Core self-evaluation was significantly associated with participation. Cancer survivors in Turkey may be more likely to believe that cancer is an inescapable destiny (Afsaroglu et al., 2010). However, cancer survivors with high levels of core self-evaluations might have higher levels of internal strength and coping resources to manage cancer-related challenges, allowing these individuals to normalize cancer experiences better than people with lower levels of core self-evaluations. Core self-evaluations may also reduce the effect of perceived public stigma on self-stigma (i.e., internalization of public stigma) allowing cancer survivors to have improved psychological adjustment and assume a more normalized lifestyle (Kim & Yi, 2014; Lebel et al., 2013).

Finally, social support and health care climate were significantly associated with participation. This finding is consistent with findings from previous studies; social support positively influences psychological adjustment to cancer, improves coping and quality of life, and, thus, is a fundamental factor for living well with cancer (Courtens, Stevens, Crebolder, & Philipsen, 1996; Filazoglu & Griva, 2008; Nazik et al., 2014; Usta, 2012). Cancer survivors in Turkey lack information about their diagnosis and are often not satisfied with the information shared with them (Guven, 2010; Khalil, 2013). However, when cancer survivors are provided more autonomy and support, they may feel closer to their health care professionals and ask specific questions and learn more about their diagnosis and treatment process (Terzioglu, 2008). In particular, close relationship with health care professionals may change cancer survivors’ perceptions about their diagnosis, increase comfort, and instill optimism to fight cancer. As cancer survivors obtain more information regarding cancer and are involved in treatment decision making, they are more likely to have internal motivation to adhere to oncology and rehabilitation treatment and have higher treatment satisfaction (Deci & Ryan, 2012; Levy, Polman, & Borkoles, 2008).

Limitations and Future Studies

Several limitations of this study must be considered when interpreting and generalizing the results. A convenience sample was used, which likely creates a biased sample of cancer survivors. For example, participants in study may have been in better health conditions, and as a result, the sample may not have been fully representative of the population. Also, the majority of the participants had breast cancer, representing a much narrower band of cancer survivors in Turkey. Furthermore, several important variables such as receipt of ongoing treatment and symptoms of posttraumatic stress disorder were not studied, which may provide additional insight into the results of the current study. However, future studies can replicate or extend the findings by conducting another study including the noted variables. Finally, this study was conducted in Turkey, and the cultural characteristics of the Turkish population may differ from other Middle Eastern countries or European countries.

Clinical Implications

As indicated by the results, education was positively associated with participation for cancer survivors. An increased focus on education for individuals who are diagnosed or recovering from cancer may contribute to an increase in participation. Therefore, health education workshops and interventions programs can be designed to increase cancer survivors’ knowledge about cancer and treatment options and teach coping skills to help survivors better manage cancer-related symptoms. Moreover, educational programs should be implemented across Turkey to improve access for those outside metropolitan areas. In addition to it, cancer-related misinformation including stigma and myths associated with cancer including beliefs such as cancer is a punishment due to a person’s own faults, cancer is always fatal; and cancer survivors are too ill to work (Daher, 2012) could undermine cancer survivors’ motivation to assume active roles in the community (Daher, 2012). Therefore, health care professionals should also aim to eliminate the negative effect of cancer-related stigma and myths by proving cancer-related correct information in health care education workshops.

Fatigue and perceived stress were impairment-related variables significantly associated with participation. As fatigue has physical and psychological components (Page & Adler, 2008), psychological interventions and behavioral management techniques provided in conjunction with medical treatment may help patients reduce cancer-related fatigue and stress. Pain and sleeping problems also contribute to fatigue, and as a result, pain management via physical therapy intervention must be considered for patients who report high levels of pain. In particular, psychological workshops and support groups can be designed to increase fatigue management skills and to reduce perceived stress among cancer survivors.

The results also revealed a strong association between role and social functioning variables and the participation level of cancer survivors in Turkey. As role and social functioning may be significantly influenced by physical, cognitive, and emotional functioning, intervention programs must focus on impairment factors that affect physical, cognitive, and emotional functioning through rehabilitation medicine and psychological interventions. For example, physical therapy, cognitive remediation therapy, and psychotherapy/psychological counseling can be employed to increase physical, cognitive, and emotional functioning. In particular, given that cancer survivors might assume dependent role and not feel a valued member of family and society, psychological interventions should focus on self-esteem-related psychological issues. If needed, family members can also be included in counseling and therapy sessions. Additional interventions, including assistive technology such as adapted cars, targeting social and role functioning can also be implemented to improve cancer survivors’ motivation and desire to actively engage in community activities and normalize their cancer experience.

Among the personal factors studied, core self-evaluations were significantly positively associated with participation. Cancer survivors with higher levels of core self-evaluations are more likely to positively evaluate themselves and have a positive outlook toward cancer. Positive psychology interventions including hope and mindfulness interventions aimed to increase generalized self-efficacy, self-esteem, emotional stability, and perceived control, which have recently gained prominence in rehabilitation, may help to increase the core self-evaluations of cancer survivors in Turkey. In addition to the core self-evaluation factors, other psychological factors–related interventions such as intervention aimed to increase resilient cancer survivors might also increase participation. Independent self-construal was significantly negatively associated with participation. Cancer survivors with more individualistic characteristics, while living in the collectivistic culture of Turkey, had low levels of participation and may desire to be more independent, thus avoiding community activities in a society where people maintain a higher level of interconnectedness and dependency on one another (Black, Mrasek, & Ballinger, 2003; Chhokar et al., 2014). Therefore, self-construal type of cancer survivors should be considered in application of physical and psychological interventions.

Social support and autonomy support were also significantly associated with participation. As previously indicated, support groups and group counseling sessions may help increase social support Turkish cancer survivors receive. However, seeking psychological help is associated with negative connotations, and people who receive psychotherapy are perceived to have mental health issues in Turkey. Therefore, cancer survivors may not seek help and avoid group or individual counseling sessions (Terzioglu, 2008). Friends, family members, and significant others may be more important sources of social support. Therefore, rehabilitation and health professionals should consider including family members such as parents, spouses, kids, and close friends in the interventions. Including friends and family members into the interventions would provide various sources of support to cancer survivors and increase their emotional functioning.

The results also indicated that autonomy support from health care professionals was effective in increasing the participation of cancer survivors. Cancer survivors who were involved in the treatment decision-making process, expressed their views, and felt cared for and understood by treatment providers had higher levels of participation. Consequently, educational sessions can be created to teach health care professionals how to provide more autonomy support to cancer survivors in Turkey. Educational sessions should train health care professionals about using self-determination theory to increase autonomous motivation of clients using culturally applicable techniques. In addition to it, cancer survivors can be asked to what extent they feel included into treatment sessions and more intervention sessions can be designed for those who report a lower level of involvement into treatment process.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

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