Abstract
INTRODUCTION: The present study aims to examine predictors of dropout, treatment outcome, and relapse of web-based guided self-help cognitive behavior therapy-enhanced (CBT-E) for binge-eating disorder. Data were collected as part of a randomized controlled trial examining the efficacy of guided self-help CBT-E. METHOD: Logistic regression analyses were performed to predict dropout and relapse. Dropout was defined as premature termination of treatment and relapses as an increase in Eating Disorder Examination-Questionnaire (EDE-Q) global score ≥ 1 SD between end of treatment and follow-up. A multiple regression analysis was conducted to predict treatment outcome using residual change scores of the EDE-Q global score between baseline, end of treatment, and between baseline and 12-week follow-up. Evaluated predictors for dropout were demographics and the presence of comorbid psychopathology; for treatment outcome and relapse, EDE frequency of binge eating, and the shape and weight concern subscales, and the presence of comorbid psychopathology. Predictors were measured at baseline. RESULTS: A total of 190 patients (90.3% female, age M = 39 years, SD = 13.3) completed the end-of-treatment assessments and 181 at follow-up. Dropout was predicted by non-Dutch ethnicity, male sex, and a lower education level. Comorbid psychopathology predicted poorer treatment outcomes at the end of treatment, but not at follow-up. No predictors of relapse were identified. DISCUSSION: Comorbid psychopathology predicted less immediate benefit from treatment, but these patients show further improvement in the 12 weeks after treatment. Future research may show if culturally sensitive and tailored interventions reduce dropout rates among individuals from non-Dutch ethnicity, males, and lower-educated patients.