Background/Rationale: Health disparities are differences in health outcomes and their determinants between segments of the population, as defined by social, demographic, environmental, and geographic attributes. Health disparities have persisted over time in the U.S. for a wide range of conditions affecting vulnerable populations. In the Veterans Health Administration (VHA), where financial barriers to receiving care are minimized, disparities are diminished, but still present for many important health outcomes. Vulnerable populations within VHA include those who are at risk for poor physical, psychological, or social health because of differences in underlying characteristics historically linked to discrimination or exclusion. Though a wide range of studies have examined disparities and gaps in care for selected conditions and vulnerable populations, there has not been a systematic evaluation of diagnosed conditions, mortality, or quality across the entire VHA healthcare user population, and therefore the extent of VHA health and quality gaps for vulnerable Veteran populations is unknown. Objectives: The QUERI-Office of Health Equity Partnered Evaluation Center has four specific aims. It seeks: (1) to assess where disparities currently exist between vulnerable Veteran VHA User groups and reference groups in morbidity and mortality for major conditions that are considered the principal causes of disability and mortality, particularly among vulnerable Veteran populations; (2) to examine gaps and trends in quality of care across treatment settings among vulnerable Veteran populations; (3) to determine the extent to which new models of care alter the association between vulnerable population status and gaps in quality of care; and (4) in partnership with VHA Office of Health Equity, to convene an Advisory Board to examine the context for and identify next steps needed to reduce disparities identified, for the purpose of informing development of action plans to reduce health disparities in VHA. Methods: We are utilizing a population health approach to examine the distribution of diagnosed health conditions, mortality, and healthcare quality across the entire Veteran VHA user population, as defined by their membership or not in vulnerable population groups. These vulnerable groups are defined by: race/ethnicity, sex, socioeconomic status, rurality of residence, service-connected disability status, serious mental illness, and age group. We will use secondary data analysis of VHA administrative data sources that builds on an existing database containing a complete multi-year cohort of VHA patients. Anticipated Impact: In recognition of the potential for policies and interventions to improve health outcomes for vulnerable populations, this Partnered Evaluation Center incorporates activities designed to use findings to support evidence-based practice and policy to reduce health disparities in VHA. This evaluation will identify high priority VHA health out...