title: Managed care plan performance since 1980. A literature analysis.
abstract: OBJECTIVE
  To compare the health care utilization, expenditure, quality of care, and satisfaction since 1980 of enrollees in managed care and indemnity plans.
  
  
  METHODS
  Studies selected met the following criteria: data from 1980 forward, private insurance or Medicare enrollees, a comparison group, a reasonable attempt at statistical adjustment for noncomparable managed care and indemnity plan enrollees, and peer-reviewed findings (with two exceptions). Few studies on preferred provider organization plan performance met the selection criteria.
  
  
  RESULTS
  Compared with indemnity plans, health maintenance organization plans had somewhat lower hospital admission rates, 1% to 20% shorter hospital length of stay, the same or more physician office visits per enrollee, less use of expensive procedures and tests, greater use of preventive services, mixed results on outcomes, and somewhat lower enrollee satisfaction with services but higher satisfaction with costs. The evidence does not support the hypothesis that prepaid group practice or staff model health maintenance organizations are more effective than individual practice association or network model health maintenance organizations.
  
  
  CONCLUSIONS
  Although this literature analysis found several clear patterns of results, several factors, including unmeasured selection bias, diverse and rapidly changing health plans and local market conditions, and relatively few research results, suggest that generalizations must be made with caution.
authors.affiliation: University of California-San Francisco, Institute for Health & Aging 94143.
authors.forename: R H
authors.initials: RH
authors.lastname: Miller
authors.forename: H S
authors.initials: HS
authors.lastname: Luft
mesh_terms: D017048:Health Care Costs / Q000706:statistics & numerical data; D005102:Health Expenditures / Q000706:statistics & numerical data; D006279:Health Maintenance Organizations / Q000191:economics / Q000592:standards / Q000706:statistics & numerical data; D006761:Hospitals / Q000706:statistics & numerical data; D015273:Insurance Selection Bias; D007902:Length of Stay / Q000706:statistics & numerical data; D008329:Managed Care Programs / Q000191:economics / Q000592:standards / Q000706:statistics & numerical data*; D006278:Medicare / Q000706:statistics & numerical data; D009819:Office Visits / Q000706:statistics & numerical data; D010343:Patient Admission / Q000706:statistics & numerical data; D017060:Patient Satisfaction / Q000706:statistics & numerical data; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data; D011331:Private Practice / Q000191:economics / Q000592:standards / Q000706:statistics & numerical data; D011787:Quality of Health Care / Q000706:statistics & numerical data; D014481:United States