Designing Trust in the Loop for Type 1 Diabetes Technology

Continuous glucose monitors, insulin pumps, and automated insulin delivery systems can improve glycemic outcomes in type 1 diabetes, but clinical efficacy alone does not ensure safe or sustained use. Users still interpret information, maintain hardware, supply context, and recover from uncertainty or failure. This structured narrative review asks how technical behavior, interaction burden, and user control can be evaluated together when studying trust in diabetes technology. Existing clinical comparison frameworks, human-factors standards, trust theory, value-sensitive design, psychosocial measures, and barrier-screening tools already address parts of this problem. The proposed Trust-in-the-Loop framework does not replace them or claim that its underlying concerns are new. Its contribution is a diabetes-specific, cross-layer evaluation map linking three layers and six proposed constructs: technical integrity (sensing integrity; bounded and recoverable automation), interaction quality (actionable feedback; embodied fit), and relational control (calibrated reliance; preserved agency). An illustrative failure scenario and four testable propositions show how one device event can propagate across these layers. The framework is conceptual and has not been clinically or psychometrically validated. Its value therefore depends on whether future research finds that the constructs are distinguishable and improve explanation of critical-task performance, burden, continued use, and safety beyond existing approaches.