PROJECT SUMMARY/ABSTRACT Type 2 diabetes (T2DM) is a leading cause of cardiovascular disease, blindness, lower extremity amputations and kidney failure in the United States, and disproportionately affects minority and low-income Americans. The Diabetes Prevention Program (DPP) effectively helps adults with prediabetes delay their progression to T2DM. However, the CDC-supported national DPP expansion has had low uptake among racial and ethnic minority and low-income adults, who are disproportionally affected by T2DM. In 2019, California legislators passed Senate Bill 97, which expanded the DPP to include Medi-Cal (California-specific Medicaid) beneficiaries. The parent grant (R18DK122372) aims to evaluate the effectiveness of this expansion on diabetes risk markers (e.g., weight change) by utilizing a large longitudinal cohort of Medi-Cal adults from Kaiser Permanente Northern California (KPNC) and the University of California, Los Angeles (UCLA), two large health systems with diverse patient populations. The results of the parent grant's main outcomes however may be modified by the coronavirus disease 2019 (COVID-19) pandemic. The mandated shelter-in-place orders, economic shut downs and pandemic-related restrictions have resulted in a decrease in exercise and increased weight gain, along with a decrease in utilization of preventive health care services. However, it is unclear the extent to which these changes disproportionally affected Medi-Cal beneficiaries, who have been hard hit by the pandemic. Leveraging three years of longitudinal data (1/1/19-12/31/21), the primary objective of this diversity supplement is to assess the extent to which the COVID-19 pandemic exacerbated disparities in T2DM prevention and outcomes between the Medi-Cal and commercially-insured populations. The career development plan for this diversity supplement will provide the candidate with high-quality mentorship from experts in T2DM prevention, health disparities, biostatistics and evaluation of natural experiments. Aligned with this plan and using the R18 parent grant retrospective cohort, the research goals of the proposed diversity supplement are to: 1) examine differential rates of T2DM screening among California adults following the COVID-19 pandemic, by insurance status (Medi-Cal vs. commercial) and demographics; 2) examine differential changes in T2DM risk factors (exercise and weight) among California adults following the COVID- 19 pandemic, by insurance status (Medi-Cal vs. commercial) and demographics; and 3) accounting for changes in screening rates, examine differential changes in T2DM incidence rate among California adults following the COVID-19 pandemic, by insurance status (Medi-Cal vs. commercial) and demographics. Understanding how Medi-Cal beneficiaries were disproportionally affected is important for allocating limited resources (including DPP) and targeted interventions. Furthermore, the mentorship, career development and scientific skills gained du...