Prior research has firmly established both that persons of lower socioeconomic status with systemic lupus erythematosus (SLE) experience poorer access to care, actual health care utilization, and outcomes due in part to the nature of their health insurance. The proposed project will assess the role that differences in quality of care play in explaining why persons with SLE from disadvantaged backgrounds have less access to care and poorer health outcomes. The project will draw upon the data from the Lupus Outcomes Study (LOS) to assess the effect of quality of care on SLE outcomes. The LOS currently includes 1,026 persons with SLE from a wide range of environments across the nation, most of whom have been followed for five years. The principal data in the LOS are data from medical charts and annual structured telephone interviews, supplemented by contextual data about the neighborhoods and medical markets of LOS participants from the Census and other publicly available data sources, matched to the survey responses by geocoding. The specific goals of the project are to: 1) describe the extent to which care for SLE adheres to measures of quality cross-sectionally and over time;2) establish the relationship between quality of care and kind and extent of health care utilization;3) document differences in quality of care by socioeconomic status, race/ethnicity, local communities, and the nature of medical markets;4) establish the relationship among such features of the health care system as type of insurance (Medicaid, Medicare, or private), form of insurance (managed care or fee-for-service), and extent of cost sharing and quality of care, after taking personal SES and extent of health care infrastructure into account;and, 5) describe the role that differences in quality of care play in explaining outcome differences by SES, including traditional measures of outcome as well as costs. The project may help reduce disparities in access and outcomes by showing that adherence to standards for quality of care can redound to the disadvantaged with SLE either by assisting their physicians to provide such care or by spurring referral to high quality providers. PUBLIC HEALTH RELEVANCE: Systemic lupus erythematosus (SLE) is a severe autoimmune disease with a potential for significant morbidity due to impacts on many organ systems. Prior research has established that persons with SLE from lower socioeconomic backgrounds have poorer access to care and long-term outcomes. The proposed project will use a cohort of over 1,000 persons with SLE followed for up to ten years to determine the extent to which the poorer outcomes of those of low socioeconomic status is because they are less likely to receive health care that meets minimal criteria for quality. The project could help persons with SLE from low socioeconomic backgrounds by showing that referral to physicians providing high quality care will reduce disparities in outcomes.