Cognitive-Behavioral and Psychodynamic Therapy in Female Adolescents With Bulimia Nervosa: A Randomized Controlled Trial

Abstract Objective The authors compared cognitive-behavioral therapy (CBT) and psychodynamic therapy (PDT) for the treatment of bulimia nervosa (BN) in female adolescents. Method In this randomized controlled trial, 81 female adolescents with BN or partial BN according to the DSM-IV received a mean of 36.6 sessions of manualized disorder-oriented PDT or CBT. Trained psychologists blinded to treatment condition administered the outcome measures at baseline, during treatment, at the end of treatment, and 12 months after treatment. The primary outcome was the rate of remission, defined as a lack of DSM-IV diagnosis for BN or partial BN at the end of therapy. Several secondary outcome measures were evaluated. Results The remission rates for CBT and PDT were 33.3% and 31.0%, respectively, with no significant differences between them (OR=0.90, CI=0.35-2.28, p=0.82). The within-group effect sizes were h=1.22 for CBT and h=1.18 for PDT. Significant improvements in all secondary outcome measures were found for both CBT (d’s=0.51-0.82) and PDT (d’s=0.24-1.10). The improvements remained stable at the 12-month follow-up in both groups. There were small between-group effect sizes for binge eating (d=.23) and purging (d=.26) in favor of CBT and for eating concern (d=-.35) in favor of PDT. Conclusion CBT and PDT were effective in promoting recovery from BN in female adolescents. The rates of remission for both therapies were similar to those in other studies evaluating CBT. This trial identified differences with small effects in binge eating, purging, and eating concern.