Treatment consolidation after vertical integration: Evidence from outpatient procedure markets.

Hospital ownership of physician practices has grown across the US, and these strategic decisions seem to drive higher prices and spending. Using detailed physician ownership information and a universe of Florida discharge records, we show novel evidence of hospital-physician integration foreclosure effects within outpatient procedure markets. Following hospital acquisition, physicians shift nearly 10% of their Medicare and commercially insured cases away from ambulatory surgery centers (ASCs) to hospitals and are up to 18% less likely to use an ASC at all. Altering physician choices over treatment setting can be in conflict with patient and payer cost, convenience, and quality preferences.