Coping Styles, Homework Compliance, and the Effectiveness of Cognitive-Behavioral Therapy

Transcription

1 Journal of Consulting and Clinical Psychology 1991, Vol. 59, No. 2, Copyright 1991 by the American Psychological Association, Inc X/91/S3.00 Coping Styles, Homework Compliance, and the Effectiveness of Cognitive-Behavioral Therapy David D. Burns Presbyterian Medical Center of Philadelphia and University of Pennsylvania School of Medicine Susan Nolen-Hoeksema Stanford University Factor analysis of the Self-Help Inventory (Burns, Shaw, & Crocker, 1987) in a group of 307 consecutive outpatients seeking cognitive-behavioral therapy (CBT) for affective disorders revealed 3 factors that assessed the frequency with which subjects used active coping strategies when depressed, the perceived helpfulness of these coping strategies, and their willingness to learn new coping strategies. The Frequency and Helpfulness scales did not predict patients' subsequent compliance with self-help assignments or their rate of improvement during the first 12 weeks of treatment. These findings suggest that very resourceful patients are not better candidates for CBT than other patients and that patients' expectations about the value of active coping strategies do not predict the response to CBT. In contrast, the Willingness scale was correlated with the degree of improvement during the first 12 weeks of treatment. The Willingness scale and compliance with self-help assignments made additive and separate contributions to clinical improvement. Further research on motivational factors may be indicated. The majority of persons with unipolar depression treated with cognitive-behavioral therapy (CBT) improve substantially (Blackburn, Bishop, Glen, Whalley, & Christie, 1981; Dobson, 1989; Elkin et al., 1989; Hollon, DeRubeis, et al., 1988; Hollon, Evans, & DeRubeis, 1988; Murphy, Simons, Wetzel, & Lustman, 1984; Persons, Burns, & Perloff, 1988; Rush, Beck, Kovacs, & Hollon, 1977; Teasdale, Fennell, Hibbert, & Amies, 1984) and maintain this improvement to a greater extent than patients treated with antidepressant medications in the year or two following therapy (Blackburn, Eunson, & Bishop, 1986; Evans et al., 1988; Kovacs, Rush, Beck, & Hollon, 1981; Simons, Murphy, Levine, & Wetzel, 1986). However, not all depressed persons respond to CBT (Blackburn & Bishop, 1983; Fennell & Teasdale, 1987), and very little is known about variables that may account for individual differences in the response to treatment. Skills at Coping With Depression A major emphasis of CBT is training depressed individuals to modify the dysfunctional patterns of thinking and behaving that may cause or prolong an episode of depression (Beck, Rush, Shaw, & Emery, 1979). Because therapists help patients to develop more adaptive attitudes and behaviors, several investigators have suggested that patients' coping styles may influence their responses to CBT (see Rude, in press, for a review). Cronbach and Snow (1977) have referred to two competing theories about the interaction between patients' pretreatment attitudes We wish to thank Jayne Stake for allowing us to use selected items from her activity checklist in the Self-Help Inventory. Correspondence concerning this article should be addressed to David D. Burns, MD, and Associates, Presbyterian Medical Center of Philadelphia, 39th and Market Streets, Philadelphia, Pennsylvania and subsequent therapy responses as the compensation and capitalization models. The compensation model suggests that patients with poor coping skills before treatment will subsequently improve the most because CBT is designed to compensate for their coping deficiencies by teaching them how to curtail self-defeating attitudes and behavior patterns (Barber & DeRubeis, 1989; Rude, in press). In contrast, the capitalization model predicts that patients with the best pretreatment coping skills will subsequently improve the most because CBT capitalizes on their strengths (Rude, in press). Thus, patients who tend to use active coping strategies before the beginning of therapy may recover more rapidly than those who do not (Bandura, 1982; Teasdale, 1985). If the compensation or capitalization hypothesis was validated, it might help in the selection of candidates most likely to respond to CBT. Recent studies by Nolen-Hoeksema and colleagues (Butler & Nolen-Hoeksema, 1990; Morrow & Nolen-Hoeksema, 1990; Nolen-Hoeksema, Morrow, & Fredrickson, 1990) of depressed individuals not receiving psychotherapy suggest that many people have consistent styles of responding to dysphoric feelings. Moreover, these coping styles seem to influence the duration of the dysphoric feelings. Individuals who use active coping strategies appear to have shorter and less severe periods of depression than do individuals who ruminate about the causes and implications of their depressed moods. These studies suggest that depressed people who enter treatment with a more active coping style may recover more rapidly than people with a more ruminative coping style. The results of a recent study by Simons and her collaborators (Simons, Lustman, Wetzel, & Murphy, 1985) were consistent with this hypothesis. In their investigation, 35 moderately depressed outpatients were randomly assigned to 12 weeks of cognitive therapy or antidepressant drug therapy. Although improvement did not differ as a function of the type of treatment received, initial scores on Rosenbaum's (1980) Self-Control

2 306 DAVID D. BURNS AND SUSAN NOLEN-HOEKSEMA Schedule (SCS) were differentially correlated with the outcome in the two groups. Patients with high SCS scores responded better to cognitive therapy, whereas those with low scores responded better to pharmacotherapy. Inasmuch as the Self-Control Schedule purportedly assesses learned resourcefulness or the capacity to solve personal problems through active efforts these findings suggest that individuals with active coping skills might recover more rapidly when treated with CBT than individuals without such skills. However, enthusiasm about the results of this study must be tempered because they were only marginally significant and were based on a stepwise regression procedure that capitalizes heavily on chance (see Hanushek & Jackson, 1977, p. 96). Therefore, a cross-validation in an independent sample is needed to determine whether attitudes about coping before treatment are correlated with the rate of subsequent recovery in CBT. Self-Help Assignments One way cognitive and behavioral therapists attempt to teach patients coping skills is through self-help assignments (Burns, Adams, & Anastopoulos, 1985). In a review of 500 clinical outcome studies appearing in eight behavior therapy journals between 1973 and 1980, Shelton and Levy (1981) found that 68% included some type of self-help assignment as part of the treatment package. Of the 20 studies that dealt specifically with depression, 50% cited some reliance on self-help assignments as a therapeutic tool. Nevertheless, there have been few systematic investigations of the efficacy of this technique. Harmon, Nelson, and Hayes (1980) provided depressed clients with nondirective weekly group therapy with or without daily self-monitoring assignments. The daily monitoring of activities was related to increases in self-reported pleasant activities and to decreases in depressed mood. Similarly, Neimeyer, Twentyman, and Prezant (1985) reported that cognitive therapy with homework produced greater improvement than cognitive therapy without homework. Patients vary greatly in their compliance with self-help homework assignments, and these differences in compliance appear to affect recovery from depression. In a study of 70 depressed patients treated with CBT, Persons et al. (1988) reported that treatment responders were more likely to complete homework assignments between sessions than were nonresponders. When controlling for other factors, the patients who consistently completed homework improved three times as much as those who did not (see also Maultsby, 1971). Individual differences in homework compliance may also account for the results of some studies showing that assigning homework does not help patients recover from depression more quickly. In an investigation of Rehm's (1977) depression treatment program, Kornblith, Rehm, O'Hara, & Lamparski (1983) evaluated self-control therapy with or without the inclusion of homework assignments. Contrary to the authors' expectations, the patients in the homework condition did not improve more than the patients who were not given homework assignments. Primakoff, Epstein, & Covi (1986) pointed out that only 50% of the patients completed their homework assignments adequately, and some patients in the no-homework condition constructed and implemented their own homework assignments. This may help to explain why the assignment of homework was not associated with improvement in the Kornblith et al. (1983) report. Expectations and Motivation Regarding the Use of Active Coping Strategies Frank (1973) has argued that the expectation that therapy will help may be the most powerful predictor of outcome, regardless of the specific techniques the therapist uses. He (Frank, 1961, 1973, 1982) has suggested that therapy will be effective when the patient feels confident in the role of the therapist as healer and when the patient buys into the therapist's beliefs about the causes of the symptoms and the procedures for their resolution (see Kazdin, 1986, p. 51). Although this hypothesis has never been directly tested in CBT, Fennell and Teasdale (1987) reported that rapidly responding patients treated with CBT were those who reported a positive response to reading a pamphlet about the principles of cognitive therapy. Although the investigators cautioned that this was only a retrospective finding in a small study, the results do suggest that patients with positive expectations about CBT may be the ones who will respond most rapidly to the treatment. One methodologic difficulty with the Fennell and Teasdale (1987) study was that patients' attitudes about CBT were assessed after their first therapy sessions. It is therefore difficult to rule out the possibility that the enthusiasm about CBT in the rapid responders may have been the result, rather than the cause, of their early improvement. In other words, once an individual begins to recover, he or she may express greater enthusiasm about life in general. If patients' expectations about the helpfulness of cognitive and behavioral coping strategies were assessed before the first treatment session, it might help to determine whether their expectations about treatment predicted their subsequent rate of improvement. A number of investigators have proposed that the motivation to engage in therapy is also an important predictor of outcome. Sifneos (1972) and Malan (1976) have described seven personality characteristics they believe would predict a positive response to short-term psychodynamic therapy. Three of these characteristics involve the patients' willingness: a willingness to participate actively in the treatment, a willingness to explore and to change, and a willingness to make sacrifices in order to improve. The results of a study by Gomes-Schwartz (1978) of variables associated with clinical improvement among therapists of several theoretical persuasions are consistent with this hypothesis. The dimension that most consistently predicted improvement was the degree to which the patient was actively involved in the therapeutic process during individual therapy sessions. However, patients' willingness to engage actively in CBT has not been previously examined as a predictor of outcome. The Current Study In the present study we assessed patients' coping styles before the beginning of therapy and their subsequent compliance with self-help assignments, as well as their response to treatment

3 EFFECTIVENESS OF COGNITIVE-BEHAVIORAL THERAPY 307 with CBT. Specifically, we predicted that subjects who used active coping styles the most frequently before beginning therapy, as well as those who anticipated that these strategies would be helpful and were the most willing to learn new coping strategies, would be more likely to comply with homework assignments throughout the course of the therapy. We also predicted that initial coping scores and subsequent homework compliance would be correlated with the degree of clinical improvement during the first 12 weeks of treatment. Finally, we predicted that when initial coping scores and homework compliance were simultaneously correlated with the degree of clinical improvement, only homework compliance would be significant. This pattern of results would suggest the following mechanism of improvement in CBT: Patients who are the most committed to coping actively with personal problems before beginning treatment will engage more actively in the treatment process and will consequently experience relatively greater clinical improvement. Scales Method Beck Depression Inventory (BDI; Beck, Ward, Mendelson, Mock, & Erbaugh, 1961). The BDI is a 21-item, self-report scale that measures the symptoms of depression. Higher scores indicate greater depression. Total scores can range between 0 (indicating no symptoms of depression) and 63 (indicating the most severe level of depression). Self-Help Inventory (SHI; Burns, Shaw, & Crocker, 1987). The SHI is a 45-item inventory that asks people what they do to cope when they are feeling depressed. It includes behavioral strategies (such as "do physical exercise" or "get busy"), cognitive strategies (such as "remind myself that my upset will eventually pass and I will feel good again"), and interpersonal strategies (such as "talk to a friend or relative that I like"). After each activity, subjects are asked how frequently they do this when they are depressed and response options are scored rarely or never (0), occasionally (1), or often (2). Subjects are also asked how helpful they think each activity might be, with the same response options. Finally, they are asked how willing they would be to try that coping activity if a therapist or trusted friend suggested it, with response options of definitely not (0), maybe (1), or definitely (2). Thus, subjects are asked to indicate the frequency with which they engage in active coping behaviors when depressed, how helpful they perceive these coping activities might be, and their willingness to try new coping activities. Procedures All patients completed a series of questionnaires that were administered by a research assistant as part of the intake procedure at the clinic before the first therapy session. These questionnaires included the BDI and the SHI, among others. The patient's Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev., DSM-HI-R, 1987; American Psychiatric Association) diagnosis and BDI scores were given to their therapist to assist in the initial clinical evaluation. However, the scores on the Self-Help Inventory were not given to the therapists at any time so that their subsequent interactions and ratings would not be affected by this information. Twelve weeks later, the patients in the longitudinal study were contacted by the research assistant and asked to complete a number of follow-up questionnaires. These included, among others, the BDI and the estimate of how frequently they had completed self-help assignments, on the average, throughout the therapy. The response options were never (rated 1), less than one day per week, on the average (2), one day per week, on the average (3), two or three days per week, on the average (4), or more than three days per week, on the average (5). At the 12-week evaluation, the therapists were also contacted and asked to verify or modify the initial diagnoses, on the basis of subsequent clinical experience. The therapists were also asked to estimate how frequently each patient had completed self-help assignments, on the average, up to that time in the therapy, using the same response options indicated above. The therapists filled out this questionnaire separately, without consulting their patients, so that independent estimates of the patients' homework compliance could be obtained. Subjects The initial group of subjects consisted of 307 consecutively evaluated outpatients who sought treatment for mood disorders at the clinic of David D. Burns. These individuals had a mean age of 36.6 years (SD = 11.6). Of this group, 52.4% were men and 47.6% were women. The mean BDI score for the group was 21.7 (SD = 10.8), indicating a moderate level of depression. Thirty-seven percent of the subjects were single, 38% were married, 4% were cohabitating, 8% were separated, 9% were divorced, 1 % were widowed, and 3% had some other arrangement. They had a mean of.99 children (SD = 1.36). Forty-two percent had family incomes of $30,000 or less, 27% had family incomes between $30,001 and $60,000, and 31 % had family incomes over $60,000. All subjects were evaluated at the time of admission to the clinic, before their first therapy session. After data on the first 93 subjects were collected, we began to follow all subsequent subjects longitudinally. The next 214 consecutively treated patients were asked if they would be willing to be retested 12 weeks after the beginning of treatment so that variables associated with the degree of recovery could be investigated. 7" tests indicated that the 214 patients in the longitudinal study did not differ significantly from the 93 patients who were studied only at the time of initial evaluation in age, severity of depression, or scores on the three coping scales. Among the 214 longitudinally studied patients, 125 (67%) provided complete data at the 12-week evaluation. These 125 patients, who constituted the group for all longitudinal analyses reported in this paper, did not differ significantly from the 61 patients with incomplete 12- week data in terms of sex, severity of depression at intake, or scores on the three coping scales. At intake, all patients were administered the Structured Clinical Interview for the DSM-III-R (SCID; Spitzer, Williams, & Gibbon, 1985) by a therapist who would not be involved in the subsequent treatment. At the 12-week follow-up, therapists were asked to verify or modify the initial diagnoses on the basis of information gained in therapy. The distribution of probable or definite Axis I diagnoses for the total sample of patients was as follows: affective disorder only (major depressive episode or dysthymic disorder), 88 patients (30.4%); anxiety disorder only (generalized anxiety disorder, panic disorder, agoraphobia, simple phobia, social phobia or obsessive compulsive disorder), 14 patients (4.8%); and mixed affective and anxiety disorder, 156 patients (53.6%). In addition, 38 patients (13.1%) carried a drug or alcohol abuse diagnosis, and 201 patients (69.6%) carried a probable or definite concomitant Axis II diagnosis. Treatment After completing the intake procedure, patients were assigned to one of 13 cognitive-behavior therapists on the basis of therapist availability as well as the patients' financial means. Therapists differed both in type and extent of professional training. They included one physician, four PhDs, seven clinical psychology graduate students with master's degrees, and one pastoral counselor. All therapists participated in 90- min weekly training conferences to develop and refine skills in cogni-

4 308 DAVID D. BURNS AND SUSAN NOLEN-HOEKSEMA tive-behavior therapy. The student therapists received additional individual case supervision in cognitive-behavior therapy on a weekly basis from the senior therapists. Cognitive therapy sessions lasted min and involved both technical and empathic interventions (Beck et al., 1979; Burns, 1980; Burns, 1989; Persons & Burns, 1985). All patients were asked to complete homework assignments between sessions, as described by Burns et al. (1985). These included activities such as recording and refuting negative thoughts, scheduling more rewarding and productive activities, and improving interpersonal communication, among others. The patients' homework assignments were reviewed by the therapists at subsequent sessions. Therapy sessions were scheduled once or twice a week, depending on the therapists' assessments of the patients' needs. The average number of therapy sessions completed at the 12-week evaluation was 12.8 (SD = 13.0). The number of therapy sessions was not correlated with recovery from depression and therefore will not be discussed further. Factor Analyses Results We performed a confirmatory factor analysis to determine whether the three types of ratings subjects made on the Self- Help Inventory represented three distinct scales of frequency, helpfulness, and willingness. Ratings of every item on all three scales were entered into the analysis. A promax rotation was used to allow the factors to be correlated. Three factors emerged using the scree criterion. Only items loading.40 or greater on the factor were considered significant. Factor 1, which accounted for 18.3% of the variance, included 44 of the 45 ratings of willingness to engage in positive coping behaviors and included none of the ratings of frequency or helpfulness. Thus, it was interpreted as tapping the subjects' willingness to use active coping strategies when depressed. Factor 2, which accounted for 6.4% of the variance, included 41 of the 45 ratings of the helpfulness of coping behaviors and none of the ratings of willingness or frequency. Thus, Factor 2 was interpreted as tapping the perceived helpfulness of active coping strategies. Factor 3, which accounted for 5.6% of the variance, included 26 of the 45 ratings of the frequency of engaging in positive coping behaviors and none of the willingness or helpfulness items. Factor 3 was interpreted as tapping the frequency with which subjects engaged in active coping strategies before treatment. Thus, the willingness, helpfulness, and frequency factors can be considered three dimensions of coping behavior. Therefore, three scales were created by adding all 45 items on each of the three scales. For all three scales, higher scores indicate more positive attitudes or more frequent use of active coping strategies. Cronbach's coefficient alpha for these scales were willingness, 0.96; helpfulness, 0.95; and frequency, Thus, all three scales appear to represent internally consistent and reliable measures. The correlations between the three coping scales were willingness and helpfulness. r(307) =.46, p <.0001; willingness and frequency, r(307) =.34, p <.0001; frequency and helpfulness, r(307) =.28, p < These correlations were similar to the corresponding correlations between the three factors. In all subsequent analyses, total scale scores rather than factor scores were used to enhance the probability that the results could be subsequently cross-validated by independent investigators. In the total group of 307 patients, the mean on the willingness scale was (SD = 14.4, range = ); the mean on the helpfulness scale was (SD = 16.7, range = ); and the mean on the frequency scale was 84.6 (SD = 13.4, range = ). Correlations As predicted, subjects who were infrequently using positive coping strategies when they entered therapy were more depressed than subjects using these strategies more frequently: r(306) = -.31, p <.0001, and they were still more depressed 12 weeks into therapy: r(l25) = -.29, p = We had also predicted that patients who were already using more coping strategies would be more likely to comply with homework assignments. This prediction was not confirmed. The frequency of subjects' use of positive coping strategies pretreatment did not predict their compliance with homework assignments, as estimated by patients or therapists: r(\ 23) =.06, ns, and r(168) =.06, ns, respectively, 12 weeks later. Subjects who were more willing to try positive coping strategies were also less depressed pretreatment, r(303) = -.24, p <.0001, and 12 weeks into treatment, r(125) = -.29, p =.0009, than subjects who were less willing. The willingness factor was not significantly correlated with therapists' or patients' estimates of compliance with self-help assignments between sessions: r(167) =.14, p =.06, and r(122) =.12, p =.17, respectively. Contrary to predictions, the helpfulness factor was not significantly correlated with initial or 12-week BDI scores or therapists' or patients' estimates of compliance with homework assignments. Finally, the therapists' and patients' estimates of homework compliance were significantly correlated, r(192) =.39, p < Neither the therapists' nor the patients' homework estimates were significantly correlated with the initial BDI scores: r(304) =.01, ns and r(210) =.01, ns, respectively. However, both homework estimates were slightly correlated with 12-week BDI scores, r(194) = -.19, p <.008, and r(213) = -.14, p =.04, respectively. To summarize, patients who at the initial evaluation had high frequency and willingness scores were less depressed initially and at the 12-week evaluation, as predicted. However, the perception that the coping strategies would be helpful was not correlated with depression scores at either time point. None of the three coping scales were significantly correlated with subsequent homework compliance, although the willingness factor was marginally significantly correlated. Homework compliance was not predicted by the severity of depression at intake but was associated with the severity of depression at the 12-week evaluation. Regression Analyses A regression analysis was performed to test the hypothesis that subjects' coping factor scores at intake would predict BDI scores 12-weeks after beginning treatment after controlling for the BDI scores at intake. The dependent variable in the equation was the 12-week BDI score. The initial BDI and the three

5 EFFECTIVENESS OF COGNITIVE-BEHAVIORAL THERAPY 309 coping scales were the independent variables. The R 2 for this equation was 37.6%: F(4, 121) = 17.60, p < The initial BDI score was significantly associated with the final BDI score, ft = 0.59, t = 6.9, p <.0001, indicating that subjects who were the most depressed initially tended to be the most depressed 12 weeks after beginning therapy. The willingness factor was also significantly associated with the final BDI, ft = -0.17, t = -2.32, p =.02, indicating that subjects were the most willing to learn new coping strategies at intake were less depressed 12 weeks after beginning therapy, even when taking the initial severity of depression into account. The helpfulness factor and the frequency factors were not significantly associated with 12- week BDI scores in this equation. A hierarchical regression analysis indicated that the initial BDI alone accounted for 33.3% of the variance in 12-week BDI scores and that the three coping scales captured an additional 4.3% of the variance. Next, regression analyses were performed to determine whether the coping factors and homework compliance estimates made additive contributions to 12-week BDI scores when controlling for the severity of depression at intake. In the first equation, patient homework estimates were included with the three coping factors and the initial BDI scores as independent variables, and 12-week BDI score was the dependent variable. The R 2 for this equation was 43.2%, F(5,116) = 17.67, p <.0001, indicating that the homework variable accounted for an additional 6.6% of the unique variance in outcome above and beyond that which was accounted for by the initial BDI and the three coping scales. The initial BDI scores were significantly correlated with 12-week BDI scores, ft =.62,1=7.56, p <.0001, as was the patients' estimate of homework compliance, ft = 2.35, / = 3.40, p = The willingness factor approached significance, ft = -0.13, / = -1.91, p =.06, in this equation, but the frequency and helpfulness variables were not correlated with 12-week BDI scores. In a second equation, the therapists' homework estimates were substituted for the estimates by the patients. The results were similar. The initial BDI and therapists' homework estimates were correlated with 12-week BDI scores, ft =.58, t = 6.07, p <.0001, and ft = -1.80, t = -2.03, p =.04, respectively. The willingness factor almost achieved significance, ft = 0.13, / = 1.61, p =. 11, but the frequency and helpfulness variables were not correlated with 12-week BDI scores. To illustrate the effects of homework compliance and the willingness variable on clinical improvement, we will use the patient equation to estimate the 12-week BDI scores for two hypothetical patients. Both patients begin therapy with BDI scores of 25, indicating a moderate level of depression. The first hypothetical patient has a moderately high initial willingness score of 128 (indicating he or she was one standard deviation higher than the mean on this measure). In addition, he or she completed the self-help assignments consistently throughout the therapy (homework score of 5). The 12-week BDI score would be estimated to be 24.6 (intercept) (25) -.13(128) (5) = A score of 11.7 would indicate that this patient had improved substantially and was nearly in the range (10 or below) considered normal. The second hypothetical patient scored 100 on the willingness factor (indicating he or she was one standard deviation below the mean on this variable). He or she rarely or never completed homework assignments between sessions. The predicted 12-week BDI score for this individual would be (25) -.13(100) (1) = The score would indicate that this patient had not improved at all during the course of therapy. 1 Discussion Within this sample of individuals seeking treatment for mood disorders, differences in the frequency of positive coping strategies before treatment were associated with the severity of depression at the time of initial referral to the clinic and 12 weeks after the beginning of therapy. Patients who more frequently used active strategies for coping with negative moods were significantly less depressed at both time points than those with low scores on this factor. These results are consistent with other studies (Nolen-Hoeksema et al., 1990) that suggest that coping activities are an important correlate of the severity of a depressed mood. Contrary to predictions, individual differences in the frequency with which patients used active coping strategies before the beginning of treatment were not correlated with subsequent compliance with self-help assignments or with the degree of recovery. These findings indicate that individuals who cope actively are not better candidates for CBT than are other individuals. The results also indicate that individuals who are not active copers are just as likely to respond to CBT and should be accepted for treatment. Patients' pretherapy expectations about the helpfulness of active coping strategies were not correlated with initial or subsequent depression, with homework compliance, or with the response to treatment. This could be because the helpfulness factor did not accurately assess patients' expectations about the benefits of CBT. Alternatively, it may be that patients' expectations before treatment do not predict therapeutic improvement. Finally, patients' perceptions may change substantially once they begin to work with their therapists, and their expectations about the helpfulness of cognitive and behavioral coping strategies early in therapy may be better predictors of subsequent improvement or homework compliance. The willingness factor did predict how much patients' depression levels declined. The more willing patients were to learn positive coping strategies, the more they recovered. The willingness to learn positive coping was not robustly correlated with homework compliance, and regression analyses showed that the willingness to help oneself and one's subsequent home- 1 To control for the possibility that patients' financial means might confound the results, we included income as a covariate and repeated all the regression analyses. Income was significantly correlated with the degree of recovery but was uncorrelated with any of the three coping scales or with homework compliance. When included as a covariate, the t statistics for the willingness scale and the homework compliance measures increased in all equations. Otherwise, the results were very similar to those presented here.

6 310 DAVID D. BURNS AND SUSAN NOLEN-HOEKSEMA work compliance made additive and separate contributions to the degree of recovery in CBT. Further studies will be needed to determine why patients with high willingness scores improve more, and whether these effects are limited to CBT. Willingness may be a general factor that predicts patients' responses to a variety of interventions (e.g., the willingness to take medications consistently, to engage in introspection, or to express one's feelings more openly). The current study cross-validates the report by Persons et al. (1988) that subjects who completed more homework assignments between sessions improved more than those who did not comply. This suggests that participation in self-help assignments may be an important ingredient of the therapeutic process. Why is the completion of self-help assignments associated with a positive response to treatment? One hypothesis would be that the assignments themselves are helpful. A second hypothesis would be that the assignments are not specifically helpful but that the patients who complete them are more cooperative and motivated to recover than those who do not. There are several limitations in the current findings. First, the homework estimates were obtained at the 12-week evaluation. Our data do not allow us to determine whether the direction of causality is from homework compliance to the severity of depression or vice versa. It could be that the completion of homework assignments enhances the rate of recovery or that patients who are doing well are more likely to complete the self-help assignments between sessions. Alternatively, when patients are doing well, they and their therapists might overestimate their homework compliance. Finally, it cannot be assumed that the results of this study of patients treated with CBT will generalize to other forms of therapy. The size of the relationships between coping styles, homework compliance, and the degree of recovery indicate small to medium effects. Although these findings are important to a growing scientific understanding of predictors of treatment outcome, it would be premature to translate them into clinical practice at this time. If the results of this study are replicated by future investigators, it would suggest that it might be useful for CBT therapists to assess patients' willingness to learn new coping skills at the time of initial evaluation and to monitor subsequent homework compliance throughout the therapeutic process. Patients with high scores should respond well to CBT. If patients are relatively unwilling to learn positive coping skills at the initial evaluation, or if they do not subsequently complete homework assignments regularly, extra effort could be directed toward explaining the potential importance of these skills and exploring the basis for the resistance. These patients may need a more persuasive introduction to CBT or an alternative form of therapy that better fits their conceptualization of their depression (see also Blackburn & Bishop, 1983; Fennell & Teasdale, 1984). Methods to increase willingness and homework compliance might also be a fruitful direction for future research. References American Psychiatric Association. (1987). Diagnostic and statistical manual of mental disorders (3rd ed., rev). Washington, DC: Author. Bandura, A. (1982). Self-efficacy mechanism in human agency. American Psychologist, 37, Barber, J. P., & DeRubeis, R. J. (1989). On second thought: Where the action is in cognitive therapy for depression. Cognitive Therapy and Research, 13, Beck, A. X, Rush, A. J., Shaw, B. F., & Emery, G. (1979). Cognitive therapy of depression. New York: Guilford Press. Beck, A. T., Ward, C. H., Mendelson, M., Mock, J., & Erbaugh, J. (1961). An inventory for measuring depression. Archives of General Psychiatry, 4, Blackburn, I. 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