Project Summary (copied from Parent Grant) Rural areas in the United States (U.S.) have exhibited higher mortality rates than urban areas since the late 1990s, a pattern known as the rural mortality penalty. Recent research has found that the rural mortality penalty continues growing due to mortality associated with preventable causes (metabolic and cardiovascular causes, alcohol use, and mental health). The expansion of Medicaid adopted by many states in the U.S. had the potential to reduce death due to these and other causes by facilitating access to healthcare to people who were not eligible under previous eligibility thresholds. While some state in the nation adopted this expansion, a process that started in 2014, others rejected it. While the adoption/rejection of this expansion is well-documented, little is known about the role the adoption of this policy at the state level impacted well-established demographic phenomenon such as the rural mortality penalty. This project requests access to restricted data to produce mortality rates for the population aged 19-64, by sex and by race/ethnicity to conduct a novel analysis of the differences observed in the rural mortality penalty employing a difference-in-difference design. The project evaluate whether the Medicaid expansion impacted the rural mortality penalty emphasizing the overall population, and disparities by sex and race/ethnicity. The project will also be the first to explore whether the COVID-19 pandemic impacted rural/urban mortality dynamics based on state-level adoption of the expansion of Medicaid by 2020. The analytic approach will combine formal and mathematical demographic methods with novel statistical models to evaluate the impact of the expansion of Medicaid in rural/urban mortality dynamics. Findings from this project will illustrate the role that state-level policies have in shaping diverging or congruent trajectories in mortality and in the face of the ongoing COVID-19 pandemic.