title: Is same-hospital readmission rate a good surrogate for all-hospital readmission rate?
abstract: BACKGROUND
  The Centers for Medicare & Medicaid Services (CMS) readmission measure is based on all-cause readmissions to any hospital within 30 days of discharge. Whether a measure based on same-hospital readmission, an outcome that is easier for hospitals and some systems to track, could serve as a proxy for the all-hospital measure is not known.
  
  
  OBJECTIVE
  Evaluate whether same-hospital readmission rate is a good surrogate for all-hospital readmission rate.
  
  
  METHODS
  The study population was derived from the Medicare inpatient, outpatient, and carrier (physician) Standard Analytic Files. Thirty-day risk-standardized readmission rates (RSRRs) for heart failure (HF) for both all-hospital readmission and same-hospital readmission were assessed by using hierarchical logistic regression models.
  
  
  METHODS
  The sample consisted of 501,234 hospitalizations in 4674 hospitals with at least 1 hospitalization.
  
  
  METHODS
  Thirty-day readmission was defined as occurrence of at least 1 hospitalization in any US acute care hospital for any cause within 30 days of discharge after an index hospitalization. Same-hospital readmission was considered if the patient was admitted to the hospital that produced the original discharge within 30 days.
  
  
  RESULTS
  Overall, 80.9% of all HF readmissions occurred in the same- hospital, whereas 19.1% of readmissions occurred in a different hospital. The mean difference between all- versus same-hospital RSRR was 4.7 +/- 1.0%, ranging from 0.9% to 10.5% across these hospitals with 25th, 50th, and 75th percentiles of 4.1%, 4.7%, and 5.2%, respectively, and was variable across the range of average RSRR.
  
  
  CONCLUSIONS
  Same-hospital readmission rate is an unreliable and biased indicator of all-hospital readmission rate with limited value as a benchmark for quality of care processes.
authors.affiliation: Department of Internal Medicine, Boston Medical Center, Boston, MA, USA.
authors.forename: Khurram
authors.initials: K
authors.lastname: Nasir
authors.forename: Zhenqiu
authors.initials: Z
authors.lastname: Lin
authors.forename: Hector
authors.initials: H
authors.lastname: Bueno
authors.forename: Sharon-Lise T
authors.initials: SL
authors.lastname: Normand
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Drye
authors.forename: Patricia S
authors.initials: PS
authors.lastname: Keenan
authors.forename: Harlan M
authors.initials: HM
authors.lastname: Krumholz
mesh_terms: D014487:Centers for Medicare and Medicaid Services, U.S. / Q000706:statistics & numerical data*; D006333:Heart Failure / Q000628:therapy; D006801:Humans; D007345:Insurance Claim Review; D010359:Patient Readmission / Q000706:statistics & numerical data*; D019984:Quality Indicators, Health Care / Q000706:statistics & numerical data*; D014481:United States