title: Impact of Risk Adjustment for Socioeconomic Status on Risk-adjusted Surgical Readmission Rates.
abstract: OBJECTIVE
  To assess whether differences in readmission rates between safety-net hospitals (SNH) and non-SNHs are due to differences in hospital quality, and to compare the results of hospital profiling with and without SES adjustment.
  
  
  BACKGROUND
  In response to concerns that quality measures unfairly penalizes SNH, NQF recently recommended that performance measures adjust for socioeconomic status (SES) when SES is a risk factor for poor patient outcomes.
  
  
  METHODS
  Multivariate regression was used to examine the association between SNH status and 30-day readmission after major surgery. The results of hospital profiling with and without SES adjustment were compared using the CMS Hospital Compare and the Hospital Readmissions Reduction Program (HRRP) methodologies.
  
  
  RESULTS
  Adjusting for patient risk and SES, patients admitted to SNHs were not more likely to be readmitted compared with patients in in non-SNHs (AOR 1.08; 95% CI:0.95-1.23; P = 0.23). The results of hospital profiling based on Hospital Compare were nearly identical with and without SES adjustment (ICC 0.99, κ 0.96). Using the HRRP threshold approach, 61% of SNHs were assigned to the penalty group versus 50% of non-SNHs. After adjusting for SES, 51% of SNHs were assigned to the penalty group.
  
  
  CONCLUSIONS
  Differences in surgery readmissions between SNHs and non-SNHs are due to differences in the patient case mix of low-SES patients, and not due to differences in quality. Adjusting readmission measures for SES leads to changes in hospital ranking using the HRRP threshold approach, but not using the CMS Hospital Compare methodology. CMS should consider either adjusting for the effects of SES when calculating readmission thresholds for HRRP, or replace it with the approach used in Hospital Compare.
authors.affiliation: *Department of Anesthesiology, University of Rochester School of Medicine, Rochester, NY †F. Edward Hebert School of Medicine, Uniformed Services University of the Health Sciences, Rochester, NY ‡Department of Surgery, University of Vermont, Burlington, VT §Department of Public Health Sciences, University of Rochester School of Medicine, Rochester, NY ¶Department of Medicine, University of Massachusetts, Boston, MA ||RAND Health, University of Rochester Medical Center, Rochester, NY.
authors.forename: Laurent G
authors.initials: LG
authors.lastname: Glance
authors.forename: Arthur L
authors.initials: AL
authors.lastname: Kellermann
authors.forename: Turner M
authors.initials: TM
authors.lastname: Osler
authors.forename: Yue
authors.initials: Y
authors.lastname: Li
authors.forename: Wenjun
authors.initials: W
authors.lastname: Li
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Dick
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016208:Databases, Factual; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009518:New York; D010359:Patient Readmission / Q000706:statistics & numerical data*; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology / Q000628:therapy; D012044:Regression Analysis; D020379:Risk Adjustment; D064876:Safety-net Providers / Q000592:standards* / Q000706:statistics & numerical data; D012923:Social Class; D013514:Surgical Procedures, Operative