A randomised controlled evaluation of an online perfectionism intervention for people with disordered eating - how perfect does it need to be?

Less help-seeking for an eating disorder is predicted by higher levels of denial of, and failure to perceive, illness severity. This research evaluates a "backdoor" approach to early intervention by investigating whether internet cognitive behaviour therapy for perfectionism can significantly improve disordered eating. Additionally, we investigated whether a more interactive intervention impacted outcomes. Participants were recruited worldwide online; 368 were screened, 172 (46.7%) met inclusion criteria (endorsed high shape, weight, or eating concerns) and randomised to an interactive (Focused Minds Program; FMP) or static PDF intervention (Centre for Clinical Intervention; CCI-P) or waitlisted (control condition). Participants completed assessments on disordered eating, perfectionism, and a range of secondary variables at the end of treatment, and 1- and 3-month follow-up. Intent-to-treat analyses indicated that, compared to control, FMP resulted in significantly lower levels of disordered eating at each assessment and CCI-P at the 1- and 3-month follow-up (respective 3-month follow-up between group effect sizes of 0.78 and 0.54). There were no significant differences between the two active interventions on any measure except depression and hated self. Results suggest an alternative approach to directly tackling disordered eating that is low-cost is effective, with a more interactive intervention producing a more rapid effect.Trials Registration: Australian New Zealand Clinical Trials Registry (ANZCTR) Trial Number: ACTRN12621001448831.