Characteristics of emergency departments serving high volumes of safety-net patients: United States, 2000.

OBJECTIVE: This report describes hospital, community, and patient factors associated with emergency departments (EDs) whose case loads are driven by "safety-net" populations. The study also explores the relationship between safety-net burden and receipt of Medicaid Disproportionate Share Hospital (DSH) Program funds.
METHODS: Linked data were analyzed from the 2000 National Hospital Ambulatory Medical Care Survey (NHAMCS), Area Resource File, and reports of Medicaid DSH payments to hospitals. NHAMCS ED visit data were aggregated to the hospital ED level (n = 376). Hospital sampling weights were used to produce national estimates of hospital EDs. Hospitals were classified into high vs. low safety-net burden based on the percent of ED visits where the expected source of payment was Medicaid or uninsured (self-pay or no charge). High- and low-burden EDs were compared along five domains: hospital characteristics; community factors; patient mix; diagnosis mix using Billings' profiling algorithm; and condition severity, visit content, and outcome.
RESULTS: Approximately one-third (36.1 percent) of U.S. EDs were classified as high safety-net burden provides. Hospitals located in the South were more likely to have a high ED safety-net burden (61.3%). High-burden EDs saw a higher percentage of cases that were either nonurgent or emergent, but primary care treatable. EDs high in uninsured burden were not necessarily high in Medicaid burden. Fewer than half of high-burden EDs received DSH payments.
CONCLUSIONS: High safety-net burden is not necessarily offset by public funding. The vast majority of EDs that serve high proportions of uninsured patients do not receive such compensation.