Unpacking weight management interventions measuring eating disorder risk in adults: coding of components of interventions in a systematic review

Introduction: Adult weight management interventions are complex; better understanding of the intervention components that may impact eating disorder (ED) risk is required. Methods: Weight management randomized controlled trials (RCTs) for adults with overweight/obesity that measured ED risk were systematically searched in four databases and two trial registries. A project-specific codebook was used to code 84 delivery features and 89 intervention strategies of trials. Individual strategies were grouped into 20 clusters which were further grouped into five broad categories. Trial investigators verified coding and narrative synthesis using descriptive statistics of findings was reported. Results: Of 14,880 identified, 58 eligible trials were coded, of which 26 trials with 64 intervention arms were verified and therefore included. Intervention arms included a mean (SD) of 24 (11) intervention strategies. Commonly used intervention strategy clusters were nutrition education (91%), dietary behavior change strategies (84%), physical activity education (81%), and dietary self-monitoring (80%). Few interventions used strategies in the category of psychological components (13–41%). The median (range) intervention duration was 27 (4–104) weeks, and contacts with participants typically included a staged approach of weekly to monthly contact. Conclusion: Adult weight management interventions are multifactorial with varying delivery features and intervention strategies. Despite this, psychological (e.g. weight stigma) and sleep-health related strategies are either rarely used or are underreported. Breaking down intervention components using our framework can help identify which strategies influence outcomes, including eating disorder risk, and inform the design and reporting of future interventions.