Financial incentives and health coaching to improve glycemic outcomes among young adults with type 1 diabetes: A factorial randomized trial (SweetGoals).

AIM: This study aimed to improve glycemic control among young adults with type 1 diabetes (T1D), an at-risk and understudied population. METHOD: N = 300 young adults with T1D recruited nationally were randomized to the factorial combination of (1) financial incentives targeting glucose checking and mealtime behaviors and (2) web health coaching focused on increasing motivation and goal setting for self-management behaviors. All received a smartphone app that accessed device data and provided weekly goal feedback. The intervention lasted 6 months. HbA1c (A1c) was assessed at baseline, +6 months, and +12 months. The mean number of glucose checking and mealtime goals met per week during the intervention were tested as mediators of intervention effects on A1c at 12 months. CLINICALTRIALS: gov: NCT04646473. RESULTS: A1c was significantly reduced from baseline to +12 months across all participants. Indirect effects of both incentives and coaching on A1c reductions were significant and partially mediated by mealtime but not glucose checking goal achievement. There was no synergistic (interaction) effect of incentives and coaching. CONCLUSION: Incentives and coaching both improved critical mealtime behavior but through different strategies. These results suggest that either intervention would be suitable for future testing and dissemination, and that lower cost of incentives may favor their prioritization.