Project Summary/Abstract There is an urgent need for effective diabetes self-management interventions that are convenient, scalable, sustainable, and able to meet the needs of diverse patients and those with limited health literacy that may be disproportionately affected by the disease. Based on our preliminary studies, My Diabetes Care (MDC) may fill this critical gap by bringing together some of the best aspects of diabetes mHealth apps and incorporating them into a patient portal intervention that was developed to be interoperable with a variety of electronic health records (EHRs) and that offers direct integration into routine care without creating additional work for healthcare teams or the need for additional staff. MDC is a multi-faceted patient portal intervention designed to help patients better understand their diabetes health data as well as promote and support self-management. Developed at Vanderbilt University Medical Center (VUMC), MDC uses infographics to facilitate users' understanding of their diabetes health data, incorporates motivational strategies and access to an online patient support community, and provides literacy level-appropriate and tailored diabetes self-care information. To ensure interoperability and optimize scalability, we built MDC using Substitutable Medical Applications, Reusable Technologies on Fast Healthcare Interoperability Resource (SMART on FHIR) that allows MDC to be installed into a wide variety of EHR platforms across the U.S. Our preliminary studies suggest MDC is acceptable, feasible, improves understanding of diabetes health measures, and increases patient activation. The objective of the proposed research is to: (1) expand MDC's display of user's diabetes health data beyond hemoglobin A1C, blood pressure, cholesterol, and flu vaccination status to include microalbumin and BMI and enhance access by creating a Spanish-language version; (2) evaluate the effects of the expanded & enhanced version of MDC on diabetes-related outcomes while demonstrating its scalability by integrating it into another health system and conducting a pragmatic randomized controlled trial in an ethnically and racially diverse patient population, and (3) examine how the effects of MDC arise by studying causal mediators. The proposed work is important because racial/ethnic minorities and those with limited health literacy are more likely to experience barriers to diabetes self-care and technology use. By designing, testing, and evaluating, MDC in diverse groups of patients including those with limited health literacy and developing a Spanish language version, we will advance the understanding of how to create patient-facing health technologies to achieve broad uptake and address health inequities. By leveraging SMART on FHIR, our project will also demonstrate the current state of the art by implementing and testing MDC without needing to rebuild it and will serve as a model for future patient portal-based interventions.