title: Does Favorable Selection Among Medicare Advantage Enrollees Affect Measurement of Hospital Readmission Rates?
abstract: Literature indicates favorable selection among Medicare Advantage (MA) enrollees compared with fee-for-service (FFS) enrollees. This study examined whether favorable selection into MA affected readmission rates among Medicare-eligible veterans following hospitalization for congestive heart failure in the Veterans Affairs Health System (VA). We measured total (VA + Medicare FFS) 30-day all-cause readmission rates across hospitals and all of VA. We used Heckman's correction to adjust readmission rates to be representative of all Medicare-eligible veterans, not just FFS-enrolled veterans. The adjusted all-cause readmission rate among FFS veterans was 27.1% (95% confidence interval [CI] = 26.5% to 27.7%), while the adjusted readmission rate among Medicare-eligible veterans was 25.3% (95% CI = 23.6% to 27.1%) after correcting for favorable selection. Readmission rate estimates among FFS veterans generalize to all Medicare-eligible veterans only after accounting for favorable selection into MA. Estimation of quality metrics should carefully consider sample selection to produce valid policy inferences.
authors.affiliation: VA Puget Sound Health Care System, Seattle, WA, USA University of Washington, Seattle, WA, USA edwin.wong@va.gov.
authors.forename: Edwin S
authors.initials: ES
authors.lastname: Wong
authors.affiliation: VA Puget Sound Health Care System, Seattle, WA, USA University of Washington, Seattle, WA, USA.
authors.forename: Paul L
authors.initials: PL
authors.lastname: Hebert
authors.affiliation: Durham VA Medical Center, Durham, NC, USA Duke University, Durham, NC, USA.
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Maciejewski
authors.affiliation: VA Puget Sound Health Care System, Seattle, WA, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Perkins
authors.affiliation: VA Puget Sound Health Care System, Seattle, WA, USA University of Washington, Seattle, WA, USA.
authors.forename: Chris L
authors.initials: CL
authors.lastname: Bryson
authors.affiliation: VA Puget Sound Health Care System, Seattle, WA, USA University of Washington, Seattle, WA, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Au
authors.affiliation: VA Puget Sound Health Care System, Seattle, WA, USA University of Washington, Seattle, WA, USA.
authors.forename: Chuan-Fen
authors.initials: CF
authors.lastname: Liu
mesh_terms: D000368:Aged; D018588:Fee-for-Service Plans / Q000706:statistics & numerical data; D005260:Female; D006333:Heart Failure / Q000628:therapy; D006801:Humans; D008297:Male; D020398:Medicare Part C / Q000706:statistics & numerical data*; D010359:Patient Readmission / Q000706:statistics & numerical data*; D014481:United States; D014493:United States Department of Veterans Affairs / Q000706:statistics & numerical data
keywords: Medicare; Veterans; readmission; risk adjustment; selection bias