Hospital outpatient payment policy: beginnings and endings.
D000556:Ambulatory Surgical Procedures / Q000191:economics*; D005102:Health Expenditures / Q000639:trends*; D006278:Medicare / Q000331:legislation & jurisprudence*; D010044:Outpatient Clinics, Hospital / Q000191:economics*; D012051:Reimbursement Mechanisms; D014481:United States