A cluster-randomized controlled trial of automated internet weight-loss programs in primary care: Role of automated provider feedback

Objective: Despite the high prevalence of obesity and associated health risks in the United States adult population, few primary care providers (PCPs) have time and training to provide weight-management counseling to their patients. This study aims to compare the effect of referral to a comprehensive automated digital weight-loss program, with or without provider email feedback, with usual care on weight loss in patients with overweight or obesity. Methods: A total of 550 adults (mean [SD], 51.4 [11.2] years, BMI = 35.1 [5.5] kg/m², 72.0% female) were enrolled through their PCPs (n = 31). Providers were randomly assigned to refer their patients to a 12-month internet weight-loss intervention only (IWL), the intervention plus semiautomated feedback from the provider (IWL + PCP), or to usual care (EUC). Weight was measured at baseline and at 3, 6, and 12 months. Results: Weight changes (mean [SE]) at 12 months were −0.92 (0.46), −3.68 (0.46), and −3.58 (0.48) kg in the EUC, IWL, and IWL + PCP groups, respectively. Outcomes were significantly different in EUC versus IWL and EUC versus IWL + PCP (p < 0.001), but not in IWL versus IWL + PCP. Conclusions: Referral by PCPs to an automated weight-loss program holds promise for patients with obesity. Future research should explore ways to further promote accountability and adherence.