Study protocol: Behavioral economics and self-determination theory to change diabetes risk (BEST Change)

Background: The Diabetes Prevention Program (DPP) and metformin can prevent or delay the onset of type 2 diabetes mellitus (T2DM) among patients with prediabetes. Yet, even when these evidence-based strategies are accessible and affordable, uptake is low. Thus, there is a critical need for effective, scalable, and sustainable approaches to increase uptake and engagement in these interventions. Methods: In this randomized controlled trial, we will test whether financial incentives and automated messaging to promote autonomous motivation for preventing T2DM can increase DPP participation, metformin use, or both among adults with prediabetes. Participants (n = 380) will be randomized to one of four study arms. Control Arm participants will receive usual care and educational text messages about preventing T2DM. Incentives Arm participants will receive the Control Arm intervention plus financial incentives for DPP participation or metformin use. Tailored Messages Arm participants will receive the Control Arm intervention plus tailored messages promoting autonomous motivation for preventing T2DM. Combined Arm participants will receive the Incentives Arm and Tailored Messages Arm interventions plus messages to increase the personal salience of financial incentives. The primary outcome is change in hemoglobin A1c from baseline to 12 months. Secondary outcomes are change in body weight, DPP participation, and metformin use. Discussion: If effective, these scalable and sustainable approaches to increase patient motivation to prevent T2DM can be deployed by health systems, health plans, and employers to help individuals with prediabetes lower their risk for developing T2DM.