Health Locus of Control and Depression in Chronic Kidney Disease: A Dynamic Perspective

Transcription

1 Health Locus of Control and Depression in Chronic Kidney Disease: A Dynamic Perspective Journal of Health Psychology Copyright 2005 SAGE Publications London, Thousand Oaks and New Delhi, Vol 10(5) DOI: / JAMIE A. CVENGROS, ALAN J. CHRISTENSEN, & WILLIAM J. LAWTON University of Iowa, USA JAMIE A. CVENGROS, MA is a graduate fellow at the University of Iowa in the Department of Psychology. ALAN J. CHRISTENSEN, PhD is a professor at The University of Iowa in the Departments of Psychology and Internal Medicine. WILLIAM J. LAWTON, MD is a professor at the University of Iowa in the Department of Internal Medicine, Division of Nephrology. Abstract Participants in the present study were 207 patients with chronic kidney disease (CKD) who completed internal HLOC and depression measures at baseline and at an approximately 16-month follow-up period. Regression results indicated that after controlling for baseline level of depression, baseline internal HLOC was not a significant predictor of depression at follow-up. However, increases in internal HLOC over the 16-month follow-up were predictive of depression at follow-up. Furthermore, this relationship was qualified by an interaction between change in internal HLOC and disease progression. These results suggest that changes in internal HLOC over time may be a particularly important determinant of adjustment for individuals whose chronic illness progresses or becomes life threatening. ACKNOWLEDGEMENTS. Research was supported in part by National Institute of Diabetes, Digestive, and Kidney Diseases grant number DK49129 awarded to Alan J. Christensen. COMPETING INTERESTS: None declared. ADDRESS. Correspondence should be directed to: JAMIE A. CVENGROS, Department of Psychology, University of Iowa, E11 Seashore Hall, Iowa City, Iowa 52242, USA. [ jamie-cvengros@uiowa.edu] Keywords depression, health locus of control, kidney disease, patient adaptation 677

2 JOURNAL OF HEALTH PSYCHOLOGY 10(5) PREVIOUS AUTHORS have suggested that locus of control plays a key role in the prediction of the physical and psychological adjustment to chronic disease (see reviews by Wallston, 1989, 1992). Many of these studies have used the Multidimensional Health Locus of Control scales (MHLC; Wallston, Wallston, & DeVellis, 1978) to examine health-specific locus of control (HLOC) expectancies. Previous research addressing the relation of HLOC to adjustment has produced mixed findings. Many earlier studies have found that higher scores on the Internal HLOC dimension are predictive of better adjustment. For example, in several studies of patients with chronic illness (e.g. cardiovascular disease, cancer, end-stage renal disease, spinal cord injuries, traumatic brain injuries and chronic pain), Internal HLOC was positively related to psychological adjustment and higher perceived health status (Blood et al., 1993; Crisson & Keefe, 1988; Frank et al., 1987; Moore & Stambrook, 1992; Pucheu, Consoli, D Auzac, Francais, & Issad, 2004; Sun & Stewart, 2000; Taylor, Helgeson, Reed, & Skokan, 1992). However, other studies have reported a less clear relationship between HLOC and adjustment to illness (e.g. de Boer, Ryckman, Pruyn, & van de Borne, 1999; Fowers, 1994; Friedman et al., 1988; Gold et al., 1991), and a few studies have found that a more external control orientation is associated with better adjustment (Burish et al., 1984; Franco et al., 2000; Jamieson, Wellisch & Pasnau, 1978). Although there has been considerable research examining the relationship between HLOC and adjustment in physical disease, the large majority of previous studies have relied on a cross-sectional design (e.g. Blood et al., 1993; Frank et al., 1987; Jenkins & Patterson, 1998; Moore & Stambrook, 1992; Pucheu et al., 2004; Sun & Stewart, 2000). Cross-sectional designs are limited in that they only suggest a concurrent relationship between HLOC and psychological adjustment and provide little information about potential causal patterns. Moreover, these studies are unable to address the issue of whether previously assessed HLOC is predictive of subsequent changes in adjustment over time or whether changes in psychological adjustment occur as a function of changes in locus of control. A small number of previous studies have examined the relationship between HLOC and adjustment prospectively (e.g. Bremer, 1995; Helgeson, 1992; van den Akker, Buntinx, Metsemakers, van der Aa, & Knottnerus, 2001). For example, in one study of patients with cardiovascular disease, Helgeson (1992) found that higher Internal HLOC was related to less psychological distress and better adjustment to illness at three-month follow-up. For those patients who were rehospitalized within these three months for a second cardiac event, the relationship between Internal control expectancies and psychosocial adjustment to illness was even stronger, suggesting even greater importance of HLOC in the face of disease progression or recurrence (Helgeson, 1992). A central issue that has not yet been adequately examined in the HLOC literature involves the possibility that change in HLOC over time is an important determinant of adjustment. As past authors have argued (Christensen, Turner, Smith, Holman, & Gregory, 1991; Taylor, 1983; Taylor, Kemeny, Reed, Bower, & Gruenewald, 2000), the extent to which patients facing a chronic disease are able to shift perceptions of control in light of disease progression or disease recurrence may be an important determinant of adaptation. For example, Taylor s (1983) Cognitive Adaptation Theory suggests that perceptions of personal control may be heightened or activated in times of psychological challenge or threat. An enhanced perception of control may help the individual to more effectively cope with an illness-related stressor such as worsening disease. To address the potential adaptive significance of changes in HLOC over time, designs providing repeated measurement of both HLOC and adjustment must be used. Contextual moderation of HLOC effects Wallston (1992) has argued that HLOC may not act directly on psychological adjustment but rather through an interaction with contextual variables. Consistent with this hypothesis, studies using the MHLC have suggested that the adaptive significance of HLOC may be dependent on contextual or situational moderators such as prognosis, severity of disease or treatment outcome (Andrykowski & Brady, 1994; 678

3 CVENGROS ET AL.: INTERNAL HLOC AND DEPRESSION Christensen et al., 1991; Christensen, Wiebe, Benotsch, & Lawton, 1996; Helgeson, 1992). For example, in a cross-sectional study of 96 patients with end-stage renal disease, Christensen et al. (1991) found that the association between HLOC and depression differed as a function of whether or not patients had experienced a failed renal transplant. Specifically, for the patients in the failed transplant group, high Internal HLOC was related to higher depression; however, in the never transplanted group, higher Internal health control was associated with lower levels of depression. Christensen et al. (1991) suggested that a mismatch between perceived level of control and actual control over healthcare outcomes may be predictive of poorer psychological adjustment to illness. However, without the advantages of a prospective research design in which HLOC is assessed prior to the contextual event (e.g. treatment failure) and is shown to predict subsequent depression, interpretation of this pattern remains speculative. Control in chronic kidney disease Chronic kidney disease (CKD) is a chronic illness that affects more than 1,000,000 Americans. CKD is marked by an inability of the kidneys to sufficiently filter the blood of excess fluid and toxins. For many patients, CKD is a progressive condition in which kidney function declines over a period of months or years ultimately leading to end-stage renal disease (ESRD) at which point kidney function is insufficient to sustain life. Patients with ESRD must receive a kidney transplant or undergo life-long renal dialysis. As with other chronic illnesses, psychological adjustment is a common concern for patients with CKD, particularly given the unpredictable and progressive disease course patients face (Christensen & Ehlers, 2002). In particular, depression is a pervasive problem among patients with CKD. A recent epidemiologic study estimated the prevalence of depression in this patient population to be nearly 20 percent (Lopes et al., 2002). Further, depression symptoms are significantly related to increased mortality and hospitalization for patients with ESRD (Lopes et al., 2002). Despite these data regarding the prevalence and clinical importance of depression and other indices of poor psychological adjustment among patients with ESRD, few studies have examined the role of HLOC or control expectancies in general in predicting adjustment in this patient population. The present study The goal of the present study was to examine the prospective effect of Internal HLOC on changes in depression in a sample of patients with progressive, chronic kidney disease utilizing a prospective, repeated measures design. Several different models of HLOC and depression were examined. One model involved evaluating the prospective effect of initial or baseline Internal HLOC level on changes in depression over an approximate 16-month period. We anticipated that higher Internal HLOC scores would be associated with lower depression at follow-up. In the second model the relationship of changes in Internal HLOC over the follow-up period to changes in depression was examined. Based on past theorizing regarding the importance of shifts in control perceptions in response to worsening disease, we anticipated that patients whose HLOC expectancies become more strongly internal over time would evidence less depression over the follow-up period. Finally, we examined the possibility that the relationship between Internal HLOC and depression might vary as a function of disease progression. That is, we examined whether changes in locus of control would be differentially associated with changes in depression among patients whose disease had progressed to end-stage requiring them to start life-sustaining dialysis during the course of the study relative to those patients whose disease has not progressed to this stage. Method Patient sample Participants were recruited from the University of Iowa Hospitals and Clinics renal medicine clinic as part of a larger longitudinal study of quality of life in chronic kidney disease. At the time of initial recruitment, all participants were being seen as patients in the renal clinic for chronic kidney disease but were not currently 679

4 JOURNAL OF HEALTH PSYCHOLOGY 10(5) receiving dialysis treatment and had not received a renal transplant. Patients were approached for inclusion in the study if their creatinine level was 3.0 or greater indicating moderate impairment in kidney function but not yet requiring renal replacement intervention (i.e. dialysis or transplantation). A total of 378 patients were initially recruited for the study. Approximately one year later, participating patients were contacted for a second time. Of the initial 378 patients, 246 returned their second set of survey materials. A response rate of 65 percent was obtained for this wave of data collection. Twenty-eight of these patients were excluded from the current analyses because they had received a kidney transplant, and 11 were excluded because information regarding disease progression was unavailable, leaving a final sample of 207 patients. For 93 of these patients, their CKD had advanced to end-stage renal disease, and they were receiving hemodialysis or peritoneal dialysis treatment. A summary of the demographic and clinical characteristics of the sample is presented in Table 1. Measures Multidimensional Health Locus of Control scales (MHLC; Wallston et al., 1978) The Internal HLOC scale from Form A of the MHLC was used as a measure of patient s beliefs regarding personal control over their health outcomes. Each item of this six-item scale was answered using a five-point Likert-type format ranging from strongly disagree to strongly agree. Scores on this scale can range from 6 to 30 with higher scores indicating stronger belief in personal control. An example of an item from this scale is, The main thing that affects my health is what I myself do. Evidence of construct validity and reliability of this scale has been previously documented (Wallston et al., 1978). For some analyses, Internal HLOC change scores (i.e. follow-up score minus baseline score) were computed and entered into the regression analyses. Beck Depression Inventory (BDI; Beck, Ward, Mendelson, Mock, & Erbaugh, 1961) The BDI was used to assess each patient s level of depression. The BDI consists of 21 items that assess several categories of depressive symptoms. The seven somatic items composing a portion of the BDI (e.g. loss of energy, fatigue, insomnia and appetite changes) may reflect physical illness rather than depression in patients with ESRD (Christensen, Turner, Slaughter, & Holman, 1989). Therefore, in the current study, parallel analyses were conducted with non-somatic BDI scores and total BDI scores, respectively. Table 1. Demographic and clinical characteristics Characteristics (n = 207) No. % Age Mean SD Gender Male Female Marital status Married Not married Diabetic status Diabetic Nondiabetic Disease progression/status at follow-up Not receiving dialysis Receiving dialysis Time since first dialysis treatment (in months) Mean 9.06 SD

5 Results Preliminary analyses A preliminary regression was conducted to examine the potential association between demographic and clinical characteristics (age, gender, years of education completed, martial status and diabetic status) with depression levels at follow-up. Using forward-entry selection, predictor variables meeting the more liberal selection criteria of p <.10 were allowed to enter the equation. The categorical predictors (i.e. gender, marital status and diabetic status) were effect coded. None of the demographic or clinical characteristics examined entered the regression model after controlling for baseline depression (all ps >.12 ). Therefore, no demographic or clinical characteristics were retained in the primary regression analyses. Correlations between the key study variables (Internal HLOC and BDI) at baseline and follow-up are presented in Table 2. Baseline Internal HLOC predicting changes in depression A hierarchical regression analysis was conducted to examine the effects of baseline Internal HLOC scores on residualized changes in depression. Baseline total BDI scores were entered on Step 1. Baseline Internal HLOC scores were entered on Step 2. As shown in Table 3, the overall regression equation was significant, R 2 =.531, F(2, 196) = , p <.01. While baseline depression emerged as a significant predictor, =.71, t(197) = 14.73, p <.01, Internal HLOC only approached significance, =.08, t(197) = 1.67, p =.09. Because of the overlap between depressive symptomatology CVENGROS ET AL.: INTERNAL HLOC AND DEPRESSION and physical symptoms of kidney disease, a parallel analysis was conducted using only the non-somatic BDI items. Essentially identical results were obtained. Baseline non-somatic depression was again a significant predictor of later depression, =.73, t(190) = 14.85, p <.01, whereas Internal HLOC again only approached significance, =.08, t(190) = 1.64, p =.10. Changes in Internal HLOC predicting changes in depression A hierarchical regression was next conducted to examine the effects of changes in Internal health locus in control on changes in depression across the follow-up periods. Baseline depression scores and Internal HLOC scores were entered on Step 1. Internal HLOC change scores (Internal HLOC at follow-up minus baseline Internal HLOC) entered on Step 2. As demonstrated in Table 4, the overall regression equation was significant, R 2 =.591, F(3, 195) = 94.11, p <.01. Baseline depression again emerged as a significant predictor of later depression, =.71, t(194) = 14.37, p <.01. In addition, after controlling for baseline depression, the Internal HLOC change score was a significant predictor of depression at follow-up, =.29, t(194) = 5.38, p <.01. An examination of the scatterplot representing changes in Internal HLOC and changes in depression suggest that patients whose Internal HLOC scores became stronger across the follow-up period reported lower depression over this period. As with the first model, essentially identical results were obtained using the non-somatic items of the BDI, including a significant effect for the Internal HLOC change score on depression at follow-up, =.26, t(188) = 4.70 p <.01. Table 2. Correlations among Beck Depression Inventory and Internal HLOC scores T1 BDI T1 IHLC T2 BDI T2 IHLC T1 BDI.153*.718*.141* (.029) i(.000) i(.045) T1 IHLC.189*.523* i(.007) i(.000) T2 BDI.342* i(.000) T2 IHLC p-values shown in parentheses. BDI = Beck Depression Inventory; IHLC = Internal HLOC * Significant at p <

6 JOURNAL OF HEALTH PSYCHOLOGY 10(5) Table 3. Baseline Internal HLOC predicting changes in depression a Step Variable Beta b R 2 ΔR 2 F to test change 1 Baseline BDI.71 c F(1, 197) = , p <.01 2 Baseline IHLC F(1, 196) = 2.80, p <.10 3 Overall model.53 F(2, 196) = , p <.01 a BDI = Beck Depression Inventory; IHLC = Internal HLOC b The beta reported in the table is the standardized regression coefficient at the point the variable entered the equation c Beta is significant (p <.05) Table 4. Changes in Internal HLOC predicting changes in depression a Step Variable Beta b R 2 ΔR 2 F to test change 1 Baseline BDI.71 c F(2, 196) = , p <.01 Baseline IHLC.08 2 Change in IHLC.29 c F(1, 195) = 28.90, p <.01 3 Overall model.59 F(3, 195) = 94.11, p <.01 a BDI = Beck Depression Inventory; IHLC = Internal HLOC b The beta reported in the table is the standardized regression coefficient at the point the variable entered the equation c Beta is significant (p <.05) Changes in Internal HLOC and depression as a function of disease progression A final regression analysis was conducted to examine the possibility that the relationship between Internal HLOC and depression varies as a function of disease progression (i.e. whether or not patients kidney disease had progressed to end-stage requiring renal dialysis). Baseline depression scores, Internal HLOC change scores and disease progression at follow-up were entered on Step 1. Disease progression was coded as ( 1) no renal replacement treatment required at follow-up and (+1) renal dialysis initiated at follow-up. A variable representing the two-way interaction between disease progression and change in Internal HLOC was entered on Step 2. Mean centered variables were used to protect against artificially induced multi-collinearity. As illustrated in Table 5, the overall regression equation was significant, R 2 =.572, F(4, 194) = 64.85, p <.01. Table 5. Changes in Internal HLOC predicting depression as a function of treatment status a Step Variable Beta b R 2 ΔR 2 F to test change 1 Baseline BDI.73 c F(3, 195) = 79.90, p <.01 IHLC change.16 c Disease progression.01 2 IHLC change X Disease progression.15 c F(1, 194) = 9.39, p <.01 3 Overall model.57 F(4, 194) = 64.85, p <.01 a BDI = Beck Depression Inventory; IHLC = Internal HLOC b The beta reported in the table is the standardized regression coefficient at the point the variable entered the equation c Beta is significant (p <.05) 682

7 CVENGROS ET AL.: INTERNAL HLOC AND DEPRESSION Significant main effects (p <.01) were again obtained for baseline depression scores and Internal HLOC change scores. The Internal HLOC change score main effect was qualified by a significant Internal HLOC change score by disease progression interaction, change in R 2 =.021, F(1, 194) = 9.39, p <.01. An additional examination of the data was conducted to delineate the nature of the significant IHLC change by disease progression interaction. The regression lines and predicted values illustrating this interaction are presented in Fig. 1. Values one standard deviation above and below the mean were used to represent high and low scores on Internal HLOC change (Mean =.07, SD = 3.83 for Internal HLOC change). Because the sample mean for degree of change on IHLOC was essentially zero, high change in Internal HLOC is indicative of increasing Internal HLOC orientation, and low change in Internal HLOC is indicative of decreasing Internal HLOC orientation. As shown in Fig. 1, Internal HLOC change scores were only related to follow-up depression for those patients whose renal impairment progressed to end-stage disease during the course of the study. Among this subset of more severely ill patients, increases in Internal HLOC scores were associated with lower levels of depression at follow-up (mean BDI = 10.23) relative to patients whose Internal HLOC scores did not change (mean BDI = 15.03). A simple main effects analysis of regression coefficients confirmed that the main effect of change of Internal HLOC, after controlling for baseline depression, was significant for the patients who started dialysis during the course of the study, t(88) = 4.41, p <.01, but not for patients who were not receiving treatment at time of follow-up, t(107)=.15. p >.80. This suggests that changes in Internal HLOC scores are only related to depression at follow-up for those patients whose disease progressed to endstage renal disease. For those patients whose disease did not progress to the point of needing treatment, changes in Internal HLOC were unrelated to depression at follow-up. Essentially identical results were obtained using only the non-somatic items of the BDI. Specifically, baseline non-somatic depression scores and Internal HLOC difference scores emerged as significant predictors of non-somatic depression at followup, ps <.01. In addition, the interaction between 15 Dialysis at follow-up No treatment at follow-up 14 BDI scores at follow-u p Decreased Internal HLOC Increased Internal HLOC Figure 1. Effects of treatment status and change in internal health locus of control on depression (BDI) at follow-up. 683

8 JOURNAL OF HEALTH PSYCHOLOGY 10(5) disease progression and Internal HLOC difference scores was a significant predictor of nonsomatic depression at follow-up, R 2 =.018, F(1, 187) = 7.70, p <.01. Discussion The present research suggests that changes in Internal HLOC may be instrumental in predicting psychological adjustment to a progressive, chronic disease. Specifically, the current study demonstrates that baseline Internal HLOC score is not a significant predictor of changes in depression from baseline to follow-up, whereas Internal HLOC change score is a significant predictor of these changes. This relationship is further qualified when examining the interactive effects of disease progression and changes in Internal HLOC. In the present sample, increases in Internal HLOC were predictive of lower depression at follow-up among patients whose illness progressed to the point of requiring dialysis treatment. These changes in Internal HLOC were unrelated to follow-up depression in patients whose disease had not progressed to this stage. This pattern is consistent with past work by Helgeson (1992), which has suggested that the relationship between internal control expectancies and adjustment to illness is strongest among patients who experience disease progression or recurrence. Moreover, these results seem consistent with Taylor s (1983) and Taylor et al. s (2000) theory of cognitive adaptation which posits that, in addition to other changing cognitions, patients may attempt to maintain or regain a sense of personal control in the face of an uncontrollable or unpredictable illness course as a way to maintain positive emotional adaptation. Two limitations of the current study may temper these conclusions. First, although 65 percent of patients returned surveys at followup, it is possible that those patients who returned their questionnaires were qualitatively different than those who did not return the questionnaires. For example, it is possible that those patients who were adjusting poorly to their illness did not return their follow-up materials. In an attempt to address this limitation, post-hoc analyses were conducted to examine the differences in baseline scores between patients who did and did not return questionnaires are follow-up. The results from these analyses are presented in Table 6. As shown in Table 6, the groups did not differ significantly on distribution of diabetic status, gender, age, baseline depression or baseline Internal HLOC (all ps >.14). Second, although Table 6. Comparison of patients who returned T2 versus those who did not return T2 684 Returns (N = 207) Non-returns (N = 132) Characteristics No. % No. % Age Mean SD Gender Male Female Diabetic status Diabetic Nondiabetic Baseline BDI score a Mean SD Baseline Internal HLOC score b Mean SD a BDI = Beck Depression Inventory b Internal HLOC = Internal scale of the Multidimensional Health Locus of Control scale

9 CVENGROS ET AL.: INTERNAL HLOC AND DEPRESSION this study does look at the dynamic nature of Internal HLOC over two time points, to further understand the relationship between changes in Internal HLOC and changes in psychological adjustment to illness it would be beneficial to assess Internal HLOC at three or more time points and over a longer follow-up period. These limitations notwithstanding, the findings of this study reflect the importance of utilizing changes in HLOC to better understand the dynamic nature of adjustment to chronic illness, rather than baseline scores, as have been employed in most previous studies. This finding is especially important given the fact that HLOC dimensions have traditionally been conceptualized as enduring attitudes or traits. While the correlation between baseline and follow-up Internal HLOC scores is moderate (r =.52), the results from the current study suggest that changes on this dimension may be a more important determinant of adjustment than static Internal HLOC levels. To our knowledge the present study is the first to prospectively examine the association of changes in Internal HLOC to changes in depression. The results suggest that an understanding of the dynamic nature of Internal HLOC and its relation to psychological adjustment may be useful in the care of patients with chronic illness. Specifically, among those patients who experience rapid disease progression, interventions aimed at increasing a patient s sense of control may be particularly beneficial. One such intervention technique could be a shift of focus from the uncontrollable aspects of the illness (e.g. necessity of dialysis treatments) to the controllable aspects (e.g. taking a more central role in self-care activities). By helping patients to focus their attention on how they can impact their health status, sense of control might be bolstered despite an otherwise largely uncontrollable disease course. The potential impact of modifying control perceptions on patient adjustment suggests the need for further research on the dynamic nature of Internal HLOC in the context of chronic, progressive illness. References Andryowski, M. A., & Brady, M. J. (1994). Health locus of control and psychological distress in cancer patients: Interactive effects of context. Journal of Behavioral Medicine, 17, Beck, A. T., Ward, C. H., Mendelson, M., Mock, J., & Erbaugh, J. (1961). An inventory for measuring depression. Archives of General Psychiatry, 4, Blood, G. W., Dineen, M., Kauffman, S. M., Raimondi, S. C. et al. (1993). Perceived control, adjustment, and communication problems in laryngeal cancer survivors. Perceptual and Motor Skills, 77, Bremer, B. A. (1995). Absence of control over health and the psychological adjustment to end-stage renal disease. Annals of Behavioral Medicine, 17, Burish, T., Carey, M., Wallston, K., Stein, M., Jamison, R., & Lyles, J. (1984). Health locus of control and chronic disease: An external orientation may be advantageous. Journal of Social and Clinical Psychology, 2, Christensen, A. J., & Ehlers, S. L. (2002). Psychological factors in end-stage renal disease: An emerging context for behavioral medicine research. Journal of Consulting and Clinical Psychology, 70, Christensen, A. J., Turner, C. W., Slaughter, J. M., & Holman, J. M. (1989). Perceived family support as a moderator of psychological well-being in end-stage renal disease. Journal of Behavioral Medicine, 12, Christensen, A. J., Turner, C. W., Smith, T. W., Holman, J. M., & Gregory, M. C. (1991). Health locus of control and depression in end-stage renal disease. Journal of Consulting and Clinical Psychology, 59, Christensen, A. J., Wiebe, J. S., Benotsch, E. G., & Lawton, W. J. (1996). Perceived health competence, health locus of control, and patient adherence in renal dialysis. Cognitive Therapy and Research, 20, Crisson, J. E., & Keefe, F. J. (1988). The relationship of locus of control to pain coping strategies and psychological distress in chronic pain patients. Pain, 35, De Boer, M. F., Ryckman, R. M., Pruyn, J. F., & van den Borne, H. W. (1999). Psychosocial correlates of cancer relapse and survival: A literature review. Patient Education and Counseling, 37, Fowers, B. J. (1994). Perceived control, illness status, stress, and adjustment to cardiac illness. Journal of Psychology, 128, Franco, K., Belinson, J., Casey, G., Plummer, S., Tamburrino, M., & Tung, E. (2000). Adjustment to perceived ovarian cancer risk. Psycho-oncology, 9, Frank, R. G., Umlauf, R. L., Wonderlich, S. A., Askanazi, G. S. et al. (1987). Differences in coping styles among person with spinal cord injury: A cluster-analytic approach. Journal of Consulting and Clinical Psychology, 55,

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