title: Evaluating the planned substitution of the minimum data set-post acute care for use in the rehabilitation hospital prospective payment system.
abstract: OBJECTIVE
  The objective of this study was to evaluate the payment implications of substituting the Minimum Data Set-Post Acute Care (MDS-PAC) for the FIM trade mark instrument for use in the planned prospective payment system (PPS) for inpatient rehabilitation hospitals. FIM trade mark is a trademark of the Uniform Data System for Medical Rehabilitation, a division of UB Foundation Activites, Inc.
  
  
  METHODS
  We used a prospective cross-sectional design using consecutive sampling.
  
  
  METHODS
  We studied all Medicare admissions with stays of 3 days or more over a 2-month period to 50 inpatient rehabilitation hospitals in 22 states.
  
  
  METHODS
  Each participating institution completed both the FIM and the MDS-PAC assessments on all participants. Items from the MDS-PAC were combined and translated to create "FIM-like" items. We assessed agreement of classification into prospective payment cells using FIM assessment data and also using MDS-PAC data. Statistical adjustments were applied to improve the level of agreement.
  
  
  RESULTS
  The mean differences between the FIM motor and cognitive scales and their MDS-PAC translations were 2.4 (mean = 45) and 0.0 (mean = 28), respectively, with scale correlations of.85 and.84. Weighted kappas on individual items ranged from.32 to.64. There were substantial hospital-specific differences in scoring. Payment cell classification using FIM data agreed with that using MDS-PAC data only 56% of the time. Twenty percent of the facilities experienced revenue shifts larger than 10%.
  
  
  CONCLUSIONS
  Despite better item-level agreement than previously observed, poor payment cell agreement and substantial revenue shifts indicated that the MDS-PAC should not be substituted for the FIM trade mark instrument in the rehabilitation hospital PPS.
authors.affiliation: Department of Health Care Policy, Harvard Medical School, Boston, Massachusetts 02115, USA. buchanan@hcp.med.harvard.edu
authors.forename: Joan L
authors.initials: JL
authors.lastname: Buchanan
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Andres
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Haley
authors.forename: Susan M
authors.initials: SM
authors.lastname: Paddock
authors.forename: Alan M
authors.initials: AM
authors.lastname: Zaslavsky
mesh_terms: D003430:Cross-Sectional Studies; D006302:Health Services Research; D006801:Humans; D006278:Medicare / Q000191:economics; D011445:Prospective Payment System; D011446:Prospective Studies; D012044:Regression Analysis; D012047:Rehabilitation Centers / Q000191:economics* / Q000706:statistics & numerical data; D019467:Subacute Care / Q000145:classification* / Q000191:economics*; D014481:United States