Economic evaluation of cognitive behavioral therapy and Internet-based guided self-help for binge-eating disorder

ObjectiveTo determine the cost-effectiveness of individual face-to-face cognitive behavioral therapy (CBT) compared to therapist guided Internet-based self-help (GSH-I) in overweight or obese adults with binge-eating disorder (BED). MethodAnalysis was conducted alongside the multicenter randomized controlled INTERBED trial. CBT (n=76) consisted of up to 20 individual therapy sessions over 4months. GSH-I (n=71) consisted of 11 modules combining behavioral interventions, exercises including a self-monitoring food diary, psychoeducation, and 2 face-to-face coaching sessions over 4months. Assessments at baseline, after 4months (post-treatment), as well as 6 and 18months after the end of treatment included health care utilization and sick leave days to calculate direct and indirect costs. Binge-free days (BFD) were calculated as effect measure based on the German version of the Eating Disorder Examination. The incremental cost-effectiveness ratio (ICER) was determined, and net benefit regressions, adjusted for comorbidities and baseline differences, were used to derive cost-effectiveness acceptability curves. ResultsAfter controlling for baseline differences, CBT was associated with non-significantly more costs (+Euro2,539) and BFDs (+40.1) compared with GSH-I during the 22-month observation period, resulting in an adjusted ICER of Euro63 per additional BFD. CBTs probability of being cost-effective increased above 80% only if societal willingness to pay (WTP) was Euro250 per BFD. DiscussionWe did not find clear evidence for one of the treatments being more cost-effective. CBT tends to be more effective but also more costly. If the societal WTP for an additional BFD is low, then our results suggest that GSH-I should rather be adopted.