Do HMOs Reduce Preventable Hospitalizations for Medicare Beneficiaries? AHRQ 08-R005
J. Basu, L. Mobley, Medical Care Research and Review, 64(5):October 2007, 544-567. Uses 2001 hospital discharge abstracts for Medicare enrollees to assess the association of HMO enrollment with preventable hospitalizations among the elderly in four States: New York, Pennsylvania, Florida, and California.