Internet-delivered eating disorder prevention: a randomized controlled trial of dissonance-based and cognitive-behavioral treatments

Objective: Individuals who exhibit maladaptive eating behaviors are unlikely to seek treatment due to concerns regarding stigma and low insight into the severity of presenting symptoms. Internet-based intervention strategies stand to increase the likelihood of treatment-seeking due to enhanced privacy and convenience of access. The purpose of this study was to evaluate two web-based programs for eating disorder prevention. Method: The current study (N=278) was a randomized clinical trial comparing the efficacy of internet dissonance-based intervention (DBI-I), internet cognitive-behavioral treatment (CBT-I) and no treatment (NT) in a high-risk sample with elevated body image concerns. Thin-ideal internalization and body dissatisfaction were evaluated as mediators of treatment effects. Results: At post-treatment, DBI-I and CBT-I led to greater reductions in body dissatisfaction, depression, and thin-ideal internalization than NT. CBT-I was more effective at reducing dieting than DBI-I, and a trend favoring CBT-I over DBI-I was detected for body dissatisfaction. Although body dissatisfaction emerged as a mediator of select treatment effects, mediation analyses for thin-ideal internalization were non-significant. Conclusions: Internet intervention is an effective mode of delivery for eating disorder prevention. While no evidence of theory-specific mechanisms was found, body dissatisfaction was identified as a mediator of treatment outcomes. Potential directions for future research include adaptation of the interventions to a mobile format and the addition of interpersonal elements (e.g., therapist guidance) to the treatment protocol.