A Randomized Controlled Study of a Dialectical Behavior Therapy Guided Self-Help Intervention for Binge Eating Disorder

STUDY OBJECTIVES AND HYPOTHESES The primary objective of this randomized controlled trial is to compare the effectiveness of two methods of administering a dialectical behavior therapy (DBT) self-help intervention in a community sample of individuals with BED in NL: guided DBT self-help (DBT-GSH) and unguided DBT self-help (DBT-USH). A third condition designed to control for non-specific or common factors (e.g., receiving a self-help book) will also be included (NS-SH). This condition will be a self-help manual focused on improving low self-esteem using CBT strategies with no reference to binge eating.

METHODS

Sample size calculation:

Power analysis was based on the primary outcome variable: frequency of binge eating episodes. Assuming the three randomized groups (DBT-USH, DBT-GSH and NS-UGS) are equivalent at baseline, a between groups ANOVA will be used to compare them at post-treatment. Based on the findings of Masson et al. (2014), assuming an effect size of 0.40 and Type 1 error rate equal to .05, a sample size of at least 21 participants per group will yield 80% power. Assuming an attrition rate of 20%, we will require 25 participants per group.

Procedure: