An Internet-based intervention for eating disorders consisting of automated computer-tailored feedback with or without supplemented frequent or infrequent support from a coach: study protocol for a randomized controlled trial

Background: Several Internet-based interventions for eating disorders have shown their effectiveness. Still, there is a need to refine such interventions given that most existing programs seem to be limited by their static 'one-size-fits-all' approach. 'Featback', an Internet-based intervention for symptoms of eating disorders provides a more individualized approach. It consists of several components (psychoeducation, a fully automated monitoring and feedback system, and support from a coach), which can be matched to participants' needs and preferences. Until now, it is unclear whether online self-help interventions for eating disorders with support are more effective than those without. The aims of the current study are i) to examine the relative effectiveness of (the different components of) Featback; ii) to examine predictors, moderators and mediators of intervention responses; iii) to report on practical experiences with Featback; and iv) to examine the cost-effectiveness of Featback. Methods/design: Individuals aged 16 years or older, with mild to severe eating disorder symptoms will be randomized to one of the four study conditions. In condition one, participants receive the basic version of Featback, consisting of psychoeducation and a fully automated monitoring and feedback system. In conditions two and three, participants receive the basic version of Featback supplemented with the possibility of infrequent (weekly) or frequent (three times a week) e-mail, chat, or Skype support from a coach, respectively. The fourth condition is a waiting list control condition. Participants are assessed at baseline, post-intervention (8 weeks), and at 3- and 6-month follow-up (the latter except for participants in the waiting list control condition). Primary outcome measures are disordered eating behaviors and attitudes. Secondary outcome measures are (eating disorder-related) quality of life, self-stigma of seeking help, self-esteem, mastery and support, symptoms of depression and anxiety, repetitive negative thinking, motivation to change, user satisfaction, compliance, and help-seeking attitudes and behaviors. Discussion: This study aims to provide more insight into the (cost-) effectiveness of Internet-based interventions for eating disorders, particularly those with and without professional support, as well as different levels of support.