Many Metro Areas Are Dominated by One or Two Health Systems

One or two hospitals or health systems controlled the entire market for general inpatient hospital care in nearly half of metropolitan areas in 2022, according to a recent KFF analysis.

Based on RAND Hospital Data and American Hospital Association survey data, the analysis found that in more than four out of five metropolitan areas across the country, one or two health systems were responsible for more than 75% of all inpatient hospital discharges in their area.

Competition can also be measured by the Herfindahl-Hirschman Index (HHI), an indicator of a market’s concentration level. Unconcentrated markets have an HHI below 1,000; moderately concentrated markets have an HHI between 1,000 and 1,800; and highly concentrated markets are those with HHIs above 1,800, according to the current merger guidelines from the Federal Trade Commission and the Dept. of Justice.