title: Discretionary hospital use and diagnostic risk adjustment of Medicare HMO capitation rates.
abstract: The health maintenance organization (HMO) industry has expressed concern that implementation of a diagnostic risk adjustment model based solely on diagnoses from inpatient hospitalizations will penalize Medicare HMOs that have been successful in controlling costs by reducing discretionary hospitalizations. This study compares the diagnostic composition of HMO and fee-for-service (FFS) hospitalizations in four states to test the proposition that lower Medicare HMO hospital admission rates are the result of lower rates of "high-discretion" hospitalizations. The empirical findings show very little difference in the proportion of Medicare HMO and FFS hospitalizations with principal diagnoses rated as high discretion, and do not suggest that Medicare HMOs have been more successful in reducing discretionary hospitalizations than nondiscretionary ones.
authors.affiliation: Gerontology Institute, University of Massachusetts at Boston 02125-3393, USA.
authors.forename: F W
authors.initials: FW
authors.lastname: Porell
authors.forename: L
authors.initials: L
authors.lastname: Gruenberg
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002204:Capitation Fee; D014487:Centers for Medicare and Medicaid Services, U.S.; D003284:Contract Services; D003953:Diagnosis-Related Groups / Q000145:classification* / Q000706:statistics & numerical data; D018588:Fee-for-Service Plans; D005260:Female; D006279:Health Maintenance Organizations / Q000191:economics / Q000331:legislation & jurisprudence / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000706:statistics & numerical data* / Q000639:trends; D006801:Humans; D008297:Male; D006278:Medicare / Q000191:economics / Q000706:statistics & numerical data*; D015233:Models, Statistical; D011907:Rate Setting and Review / Q000379:methods; D020379:Risk Adjustment / Q000331:legislation & jurisprudence / Q000379:methods*; D014481:United States