Commitment to Treatment Goals in Prediction of Group Cognitive Behavioral Therapy Treatment Outcome for Women With Bulimia Nervosa

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1 Page 1 of 10 Journal of Consulting and Clinical Psychology June 2000 Vol. 68, No. 3, by the American Psychological Association For personal use only--not for distribution. Commitment to Treatment Goals in Prediction of Group Cognitive Behavioral Therapy Treatment Outcome for Women With Bulimia Nervosa Melissa Pederson Mussell Graduate Department of Professional Psychology University of St. Thomas James E. Mitchell Neuropsychiatric Research Institute Ross D. Crosby Neuropsychiatric Research Institute Jayne A. Fulkerson Department of Psychology University of Minnesota Harry M. Hoberman PACIFICA Center John L. Romano Department of Educational Psychology University of Minnesota ABSTRACT The purpose of this study was to investigate potential client variables that predict favorable response to group cognitive behavioral therapy in a sample of women ( N = 143) seeking treatment for bulimia nervosa. Similar to findings of previous studies, bulimic symptom remission at end of treatment was predicted by baseline degree of bulimic symptom severity but not by depressive symptomatology or perfectionism. After these variables were controlled for, both pretreatment ratings of desire to discontinue bulimic behaviors and expected success significantly added to prediction of treatment outcome. The primary variable found to predict longer term outcome was symptom remission at the end of treatment and at the 1-month follow-up. The body of bulimia nervosa (BN) treatment literature supports the claim that cognitive behavioral therapy (CBT) is efficacious in reducing bulimic symptom severity for many individuals with BN (see review by Wilson, Fairburn, & Agras, 1997 ). However, heterogeneity of treatment response also has been demonstrated consistently in that many participants remain symptomatic at the end of treatment and therapeutic gains may not be well maintained for some individuals (see reviews by Mitchell, Hoberman, Peterson, Mussell, & Pyle, 1996, and Wilson, 1996 ). Yet very few controlled CBT trials have reported data on predictors of BN treatment outcome. Furthermore, investigations of client-related prognostic indicators for CBT for BN have yielded few consistent predictors of BN treatment response or relapse (cf. Keel & Mitchell, 1997 ), which may be related in part to several methodological limitations. Differential criteria used to determine treatment success and variations in selection of potential predictor variables make comparisons across studies difficult. Some prediction studies have combined data from disparate treatment conditions, and numerous predictor variables were examined using modest sample sizes, resulting in large variable-to-participant ratios in many studies. Follow-up measures often were not included in the analyses. The limited number of studies available on CBT posttreatment prediction of longer term BN outcome has focused on prediction of relapse ( Fairburn, Peveler, Jones, Hope, & Doll, 1993 ; Freeman, Beach, Davis, & Solyom, 1985 ; Olmsted, Kaplan, & Rockert, 1994 ), suggesting that residual symptoms of BN (e.g., vomiting and body image disturbance) at the end of treatment may be predictive of less favorable long-term outcome; however, data are not

2 Page 2 of 10 reported for prediction of longer term outcome for those individuals deemed not to have met the various criteria for successful recovery in each study, limiting the sample size and contributing to a restricted range of symptom severity. Several client variables related to commitment to treatment have been found to predict outcome in other areas of psychology (especially addictive behaviors), including issues related to motivation and readiness to change ( Prochaska & DiClemente, 1986 ; Prochaska, DiClemente, & Norcross, 1992 ), expectations for therapy (see review by Garfield, 1994 ), and self-efficacy (e.g., DiClemente, Prochaska, & Gilbertini, 1985 ; Garcia, Schmitz, & Doerfler, 1990 ). Client variables such as these have rarely been investigated in the area of BN psychotherapy outcome. The purpose of the present study was to investigate the prognostic contribution of several client variables in predicting outcome to CBT in a relatively large sample from a National Institute of Mental Health funded BN treatment study. In addition to including variables that have been examined in previous BN studies (e.g., bulimic symptom severity, depressive symptomatology, perfectionism, and ineffectiveness), this project investigated measures of client commitment to treatment goals. Pretreatment variables were used to predict response to treatment (i.e., symptom remission) at treatment completion; posttreatment and 1-month follow-up variables were used to predict longer term outcome. Participants Method Participants ( N = 143) were adult women enrolled in a BN group CBT treatment study at the Eating Disorders Research Program of the University of Minnesota who met the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987 ) criteria for BN, with the additional criterion of engaging in binge eating and purging (i.e., self-induced vomiting and/or laxative abuse) a minimum of three times per week for 6 months prior to enrollment. Details of the sample demographics, procedures, intervention, and treatment outcome results of this project have been published elsewhere ( Mitchell et al., 1993 ; see also Crosby et al., 1993, for secondary analyses). Therapeutic Intervention Treatment consisted of 12 weeks of group-administered CBT. Psychotherapy sessions were highly structured and followed two manuals: the manual for the Healthy Eating Meal Planning System ( Boutacoff, Zollman, & Mitchell, 1986 ) and the Bulimia Nervosa Group Treatment Manual ( Eating Disorders Research Program, 1985 ). Participants were randomly assigned by group to treatment condition on the basis of a four-cell design in which treatment groups differed on two dimensions: emphasis on early abstinence (high vs. low) and treatment intensity (i.e., frequency of visits and high vs. low). Measures The Thoughts About Abstinence Scale (TAAS) was modified for use with BN 1 from the scale that was adapted by Hall, Havassy, and Wasserman (1990) from Marlatt (1979 ; Marlatt, Curry, & Gordon, 1988 ) for substance abuse. It consists of four items that assess various dimensions of commitment to treatment goals (i.e., discontinuing bulimic behaviors), including client ratings of intensity of desire to quit, expected success at quitting, predicted difficulty in quitting, and treatment goal regarding abstinence. 2

3 Page 3 of 10 The Eating Behaviors III (EB III; Mitchell, Hatsukami, Eckert, & Pyle, 1985 ), a self-report instrument used to assess weekly frequency of bulimic behaviors, was administered throughout the study. Degree of depressive symptomatology was assessed with the 21-item Beck Depression Inventory (BDI; Beck, Ward, Mendelson, Mock, & Erbaugh, 1961 ). The Eating Disorder Inventory (EDI; Garner & Olmsted, 1984 ; Garner, Olmsted, & Polivy, 1983 ), a 64-item, self-report inventory designed to assess various aspects of eating-disordered psychopathology, was also administered. Two of the eight rationally derived subscales, Perfectionism and Ineffectiveness, were selected for the present investigation because they represent constructs related to self-concept that may potentially moderate response to treatment but are not direct measures of treatment commitment. Procedure After initial telephone screening and obtaining written informed consent, potentially eligible participants were evaluated 3 by one of the study psychiatrists. Qualified participants were randomly assigned to treatment condition. All of the baseline measures were obtained prior to beginning CBT. Participants completed the EB III weekly throughout treatment and the EB III, the TAAS, the BDI, and the EDI at the end of treatment. Follow-up information was collected in person 1 month and 6 months after treatment completion. Weekly self-monitoring forms were used to assess frequency of eating behaviors for the past month at the 1-month follow-up. Recall reports for the past month were used to assess frequency of eating behaviors at the 6-month follow-up. Statistical Analyses Treatment outcome was measured as dichotomous criterion variables (i.e., symptom remission vs. symptomatic) 4 using the EB III. Symptom remission was defined as total absence of binge eating or purging (i.e., vomiting or laxative use) behavior for the past 2 weeks at the end of treatment and for the past month for longer term outcome; all other outcomes were defined as symptomatic. The last data point was used in cases of premature termination, resulting in all such cases being categorized as symptomatic. Hierarchical multiple logistic regression with sequential blocks of variables ( Cohen & Cohen, 1983 ) and simultaneous entry of variables in each block was used to test the contribution of variables to outcome prediction. Statistical significance was determined using p <=.05 for each step in the regression equations. Two sets of analyses were conducted. The first set of analyses tested the contribution of client pretreatment ratings of commitment to treatment goals to the prediction of outcome at the end of treatment after accounting for other relevant pretreatment predictor variables (i.e., baseline symptom severity, depressive symptomatology, and perfectionism) and treatment conditions. 5 The second set of analyses tested the contribution of client ratings of commitment to treatment goals to prediction of outcome at the 6-month follow-up after accounting for other relevant posttreatment predictor variables (i.e., posttreatment status of symptom remission, depressive symptomatology and perfectionism, and symptom remission at the 1-month follow-up). Pretreatment Results Descriptive statistics for pretreatment predictor variables are presented in Table 1. Ratings of commitment to treatment goals indicate that participants reported a high degree of desire to discontinue bulimic behaviors and high expectation of success, although they also reported a relatively high expected level of difficulty quitting. The majority of the participants (94%) reported having chosen a treatment goal of total abstinence (with 54% realizing the possibility of an occasional "slip"); few participants (6%) reported treatment goals that did not include total abstinence of bulimic behaviors.

4 Page 4 of 10 End of Treatment As shown in Table 1, attrition rates were modest, with the majority of the participants ( n = 123, or 86%) completing treatment. Among the participants who completed treatment, 50% achieved symptom remission (i.e., reported no episodes of binge eating or purging within the past 2 weeks), representing 43% of the intent-to-treat sample. Higher BDI scores, F (1, 141) = 8.90, p <.003, and greater ratings of anticipated difficulty discontinuing bulimic behaviors, F (1, 141) = 5.50, p <.021, were observed for those who dropped out of treatment, although neither of these baseline variables significantly predicted premature termination from treatment in preliminary regression analyses. The results of the initial, intent-to-treat hierarchical multiple logistic regression analysis 6 are presented in Table 2. After entering treatment conditions (Step 1), it was found that vomiting frequency and the BDI total score (entered together in Step 2) predicted symptom remission, although most of the variance in the second block was accounted for by vomiting rather than the BDI score. Perfectionism (Step 3) did not result in significant improvement of the classification model. Increased ratings of desire to stop and higher expectation of success (entered in the final step 7 ) also added significantly to the classification model, predicting posttreatment symptom remission. Follow-Up Results Outcome data were available for 89% of the participants ( n = 110) who completed treatment at the 1- month follow-up and 77% of the participants ( n = 95) who completed treatment at the 6-month followup, representing 77% and 66%, respectively, of the initial treatment sample. Of the participants who completed treatment and provided 1-month follow-up data, 26% ( n = 28) reported complete remission of bulimic symptoms for the past month at the 1-month follow-up and 27% ( n = 26) reported complete remission of bulimic symptoms for the past month at the 6-month follow-up. Table 3 depicts the results of the second hierarchical multiple regression analysis. After entering treatment conditions (Step 1), it was found that status of symptom remission (Step 2) resulted in significant improvement of the classification model. Entering the BDI total score and Perfectionism (Step 3) and ratings of commitment to treatment goals (Step 4) did not significantly improve the classification model. However, status of symptom remission at the 1-month follow-up (Step 5) resulted in significant improvement of the classification model. As depicted in Table 4, posttreatment 2-week symptom remission was associated with the majority (86%) of the participants who reported full symptom remission at the 1-month follow-up and 69% of the participants for the past month at the 6-month follow-up. Idiographic comparisons of follow-up symptom remission status indicated that 53% of the participants reporting remission at the 1-month follow-up were also in remission at the 6-month follow-up; however, of the participants classified as symptomatic at the 1-month follow-up, 80% were also symptomatic at the 6-month follow-up. Discussion The results of this study suggest that clients reporting more severe bulimic symptom severity and those indicating ambivalence or pessimism about the potential for recovery on seeking treatment may be less likely to benefit, at least immediately or exclusively, from this form of treatment. The findings that pretreatment desire to recover from BN and expectations of therapeutic success are predictive of favorable treatment response are consistent with findings reported in the substance abuse literature ( Hall et al., 1990 ; Hall, Havassy, & Wasserman, 1991 ). These client variables are likely to be related to the importance of "readiness to change" ( Prochaska & DiClemente, 1986 ; Prochaska et al., 1992 ) and self-

5 Page 5 of 10 efficacy theory ( Bandura, 1982, 1986 ) in determining treatment outcome and highlight the importance of addressing client commitment to treatment goals as part of the therapeutic process in BN treatment. The results of the prognostic value of the remaining baseline variables examined in this study are consistent with those of most other BN prediction studies. The prognostic value of commitment to treatment goals appears to be specific to desire to recover and expectations of success, as opposed to the more general concept of perfectionism, which has not been found to predict outcome in other studies ( Garner et al., 1990 ; Maddocks & Kaplan, 1991 ). Also similar to most other BN prediction studies, baseline depressive symptomatology was not found to predict treatment response. However, it is important to note that premature termination from treatment was associated with increased BDI scores and ratings of greater anticipated difficulty in discontinuing bulimic behaviors, highlighting the importance of considering augmenting treatment in such cases. The results of this study confirm the most robust finding in BN prediction studies: that severity of bulimic symptoms is a strong predictor of treatment outcome. Although the results of this investigation indicate that participants are unlikely to become asymptomatic at follow-up if they have not achieved symptom remission by treatment completion, the prognostic value of symptom remission at the end of treatment is of limited utility in predicting who will maintain clinical improvement (i.e., remain symptom free) over the course of 6 months. However, the finding that status of symptom remission at the 1-month follow-up adds to the prediction of longer term outcome yields important information: Although it is difficult to predict who will continue to be symptom free 6 months after treatment, individuals who report experiencing binge eating or purging within the 1st month after completing treatment are less likely to report symptom remission at longer term follow-up. Therefore, presence of binge eating or purging within 1 month of treatment completion may indicate that an individual is unlikely to become symptom free in the next several months without additional intervention. These findings point to the importance of investigating the benefits of a continuous care model for this disorder. Generalizability of the findings of this study are limited by several factors, including homogeneity of the sample demographics and stringent exclusion criteria ( Mitchell, Maki, Adson, Ruskin, & Crow, 1997 ). The use of stringent outcome criteria is consistent with the finding in this study that the majority of the participants (94%) endorsed a treatment goal of total abstinence from bulimic behaviors. In addition, although considerable overlap exists between the manualized CBT administered in this and other BN treatment studies, it is yet to be determined if client variables determined to predict outcome in this study are prognostically relevant when examined in other CBT research programs or in clinical settings because of concerns about external validity ( Seligman, 1995 ). Replication of the prognostic importance of client pretreatment commitment to treatment goals regarding treatment outcome is needed. Including specific measures of client readiness to change or self-efficacy might be additionally informative. Knowledge of pretreatment prognostic variables may allow professionals working with individuals seeking treatment for BN to more accurately determine if treatment using CBT (as applied in these studies) is likely to be sufficient. Wilson et al. (1997) have written about the importance of the therapist's role in enhancing motivation to change and commitment to recovery. However, methods for modifying these client variables have received little empirical attention in psychotherapy outcome literature. Clinical application of CBT might be enhanced by findings from future studies investigating therapist involvement in fostering and maintaining commitment to treatment goals. References

6 Page 6 of 10 Agras, W. S., Crow, S. J., Halmi, K. A., Mitchell, J. E., Wilson, G. T. & Kraemer, H. C. (2000). Outcome predictors for the cognitive behavioral treatment of bulimia nervosa. (Manuscript submitted for publication) American Psychiatric Association. (1987). Diagnostic and statistical manual of mental disorders ((3rd ed., rev.). Washington, DC: Author) Bandura, A. (1982). Self-efficacy mechanisms in human agency. American Psychologist, 37, Bandura, A. (1986). Social foundation of thought and action: A social cognitive theory. (Englewood Cliffs, NJ: Prentice Hall) Beck, A. T., Ward, C. M., Mendelson, M., Mock, J. E. & Erbaugh, J. K. (1961). An inventory for measuring depression. Archives of General Psychiatry, 4, Boutacoff, L. I., Zollman, M. R. & Mitchell, J. E. (1986). Healthy eating: Meal planning food lists. (Minneapolis: University of Minnesota, Psychiatry Department) Cohen, J. & Cohen, J. (1983). Applied multiple regression/correlation analysis for the behavioral sciences ((2nd ed.). Hillsdale, NJ: Erlbaum) Crosby, R. D., Mitchell, J. E., Raymond, N., Specker, S., Nugent, S. M. & Pyle, R. L. (1993). Survival analysis of response to group psychotherapy in bulimia nervosa. International Journal of Eating Disorders, 13, DiClemente, C. C., Prochaska, J. O. & Gilbertini, M. (1985). Self-efficacy and the stages of self-change in smoking. Cognitive Therapy and Research, 9, Eating Disorders Research Program. (1985). Bulimia nervosa group treatment manual. (Minneapolis: University of Minnesota, Psychiatry Department) Fairburn, C. G., Peveler, R. C., Jones, R., Hope, R. A. & Doll, H. A. (1993). Predictors of 12-month outcome in bulimia nervosa. British Journal Clinical Psychology, 26, Freeman, R. J., Beach, B., Davis, R. & Solyom, L. (1985). The prediction of relapse in bulimia nervosa. Journal of Psychiatry Research, 19, Garcia, M. E., Schmitz, J. M. & Doerfler, L. A. (1990). A fine-grained analysis of the role of selfefficacy in self-initiated attempts to quit smoking. Journal of Consulting and Clinical Psychology, 58, Garfield, S. L. (1994). Research on client variables in psychotherapy.(in A. E. Bergin & S. L. Garfield (Eds.), Handbook of psychotherapy and behavior change (2nd ed., pp ). New York: Wiley.) Garner, D. M. & Olmsted, M. P. (1984). Manual for the Eating Disorder Inventory (EDI). (Odessa, FL: Psychological Assessment Resources) Garner, D. M., Olmsted, M. P., Davis, R., Rockert, W., Goldbloom, D. & Eagle, M. (1990). The association between bulimic symptoms and reported psychopathology. International Journal of Eating Disorders, 9, Garner, D. M., Olmsted, M. P. & Polivy, J. (1983). The Eating Disorder Inventory: A measure of cognitive behavioral dimensions of anorexia nervosa and bulimia.(in P. Darby, P. Garfinkel, D. Garner, & D. Coscina (Eds.), Anorexia nervosa: Recent developments (pp ). New York: Alan R. Liss.) Hall, S. M., Havassy, B. E. & Wasserman, D. A. (1990). Commitment to abstinence and acute stress in relapse to alcohol, opiates, and nicotine. Journal of Consulting and Clinical Psychology, 58, Hall, S. M., Havassy, B. E. & Wasserman, D. A. (1991). Effects of commitment to abstinence, positive moods, stress, and coping on relapse to cocaine use. Journal of Consulting and Clinical Psychology, 59, Keel, P. K. & Mitchell, J. E. (1997). Outcome in bulimia nervosa. American Journal of Psychiatry, 154, Maddocks, S. E. & Kaplan, A. S. (1991). The prediction of treatment response in bulimia nervosa: A study of patient variables. British Journal of Psychiatry, 159, Maddocks, S. E., Kaplan, A. S., Woodside, D. B., Langdon, L. & Piran, N. (1992). Two year follow-up of bulimia nervosa: The importance of abstinence as the criterion of outcome. International Journal of

7 Page 7 of 10 Eating Disorders, 12, Marlatt, G. A. (1979). Smoking Cessation Questionnaire. (Unpublished manuscript) Marlatt, G. A., Curry, S. & Gordon, J. R. (1988). A longitudinal analysis of unaided smoking cessation. Journal of Consulting and Clinical Psychology, 56, Mitchell, J. E., Hatsukami, D., Eckert, E. D. & Pyle, R. (1985). Eating Disorders Questionnaire. Psychopharmacology Bulletin, 21, Mitchell, J. E., Hoberman, H. M., Peterson, C. B., Mussell, M. & Pyle, R. L. (1996). Research on the psychotherapy of bulimia nervosa: Half empty or half full? International Journal of Eating Disorders, 20, Mitchell, J. E., Maki, D. D., Adson, D. E., Ruskin, B. S. & Crow, S. J. (1997). The selectivity of inclusion and exclusion criteria in bulimia nervosa treatment studies. International Journal of Eating Disorders, 22, Mitchell, J. E., Pyle, R. L., Pomeroy, C., Zollman, M., Crosby, R., Seim, H., Eckert, E. D. & Zimmerman, R. (1993). Cognitive behavioral group psychotherapy of bulimia nervosa: Importance of logistical variables. International Journal of Eating Disorders, 14, Mussell, M. P. & Crosby, R. D. (1996). [Psychometric properties of the Thoughts About Abstinence Scale as modified for the use with eating disorders].(unpublished raw data) Olmsted, M. P., Kaplan, A. S. & Rockert, W. (1994). Rate and prediction of relapse in bulimia nervosa. American Journal of Psychiatry, 151, Peterson, C. B., Mitchell, J. E., Engbloom, S., Nugent, S., Mussell, M. P., Crow, S. J. & Milter, J. P. (1998). Group cognitive behavioral treatment of binge eating disorder: A comparison of therapist-led vs. self-help formats. International Journal of Eating Disorders, 24, Prochaska, J. O. & DiClemente, C. G. (1986). Toward a comprehensive model of change.(in W. R. Miller & N. Heather (Eds.), Treating addictive behaviors: Process of change (pp. 3 27). New York: Plenum Press.) Prochaska, J. O., DiClemente, C. G. & Norcross, J. C. (1992). In search of how people change: Applications to addictive behaviors. American Psychologist, 47, Seligman, M. E. P. (1995). The effectiveness of psychotherapy: The Consumer Reports study. American Psychologist, 50, Wilson, G. T. (1996). Treatment of bulimia nervosa: When CBT fails. Behaviour Research and Therapy, 34, Wilson, G. T., Fairburn, C. G. & Agras, S. W. (1997). Cognitive behavioral therapy for bulimia nervosa.(in D. M. Garner & P. E. Garfinkel (Eds.), Handbook of treatment for eating disorders (2nd ed., pp ). New York: Guilford Press.) 1 Reliability estimates for using the TAAS with an eating disorder population is supported by unpublished data ( Mussell & Crosby, 1996 ) from a binge eating disorder treatment trial ( Peterson et al., 1998 ) that indicated 2-week test retest reliability estimates ranging from.57 to.60. Unpublished data ( Mussell & Crosby, 1996 ) from a BN treatment trial ( Agras et al., 2000 ) indicate correlations in the anticipated direction for treatment completion and treatment response for all scales (although correlations were modest, ranging from.10 to.33). 2 The fourth item, abstinence goal, was transformed into a categorical variable that included the following three categories: absolute abstinence, total abstinence with realistic expectations for a slip, or goals not including total abstinence.

8 Page 8 of 10 3 Evaluation consisted of a psychiatric diagnostic interview, physical examination, laboratory tests, and electrocardiogram. 4 Diverse definitions of treatment outcome are found in the BN treatment prediction literature. The decision to select a dichotomous criterion variable was based on the clinical importance of the hypotheses under investigation (i.e., favorable treatment response) and coherence with the statistical assumptions of logistic regression that were used because of skewed data. Rationale for selecting the stringent criterion of symptom remission is supported by the finding reported by Maddocks, Kaplan, Woodside, Langdon, and Piran (1992) that complete symptom remission is more closely associated with favorable adjustment than partial symptomatology. 5 The prognostic significance of two therapeutic approaches (i.e., treatment intensity and emphasis on early abstinence) that separately and by interaction were associated with treatment effects in the previously reported efficacy study using this data set ( Mitchell et al., 1993 ) were examined to control for differences in treatment approach and to replicate previous findings. 6 Ineffectiveness was not included in the logistic regression analyses to avoid spurious results due to multicollinearity, given the high correlation ( r =.80) between Ineffectiveness on the EDI and degree of depressive symptomatology on the BDI in this sample. 7 Two of the TAAS items (i.e., predicted difficulty of quitting bulimic behaviors and abstinence goal), which were not found to predict outcome in a preliminary logistic regression analysis, were excluded from this step of the equation. This research was supported in part by an Eating Disorders Research Grant from the McKnight Foundation and by Grant DK50456 from the National Institutes of Health Obesity Research Center. Preparation for this article was facilitated by the Ruth Eckert Scholarship. Portions of this article were presented at a meeting of the Eating Disorders Research Society, Pittsburgh, Pennsylvania, November This article is based on Melissa Pederson Mussell's doctoral dissertation, conducted under the supervision of John L. Romano and the guidance of James E. Mitchell and Harry M. Hoberman and submitted to the Graduate School of the University of Minnesota. Appreciation is extended to the additional doctoral committee members: Patricia McCarthy Veach and Thomas Skovholt.

9 Page 9 of 10 We acknowledge the members of the University of Minnesota Eating Disorders Research Program, especially Dorothy Hatsukami and Carol Peterson, for their contributions to this project. Correspondence may be addressed to Melissa Pederson Mussell, Graduate Department of Professional Psychology, University of St. Thomas, 1000 LaSalle Avenue, Minneapolis, Minnesota, Electronic mail may be sent to mpmussell@stthomas.edu Received: July 13, 1998 Revised: August 12, 1999 Accepted: October 11, 1999 Table 1. Descriptive Statistics of Pretreatment Predictor Variables, Treatment Completion, and Outcome Variables Table 2. Hierarchical Multiple Logistic Regression Analyses: Pretreatment Symptom Severity, Depressive Symptomatology, Perfectionism, and Ratings of Commitment to Treatment Goals in Predicting Symptom Remission at End of Treatment Table 3. Hierarchical Multiple Logistic Regression Analyses: Posttreatment and 1-Month Follow-Up Predictors of Remission at the 6-Month Follow-Up

10 Page 10 of 10 Table 4. Status of Symptom Remission at the 1- and 6-Month Follow-Ups According to Posttreatment Status of Symptom Remission