title: A comparison of clinical outcomes from carotid artery stenting among US hospitals.
abstract: BACKGROUND
  The Centers for Medicare and Medicaid Services require hospitals performing carotid artery stenting (CAS) to recertify the quality of their programs every 2 years, but currently this involves no explicit comparisons of postprocedure mortality across hospitals. Hence, the current recertification process may fail to identify hospitals that are performing poorly in relation to peer institutions. Our objective was to compare risk-standardized procedural outcomes across US hospitals that performed CAS and to identify hospitals with statistically high postprocedure mortality rates.
  
  
  RESULTS
  We conducted a retrospective cohort study of Medicare beneficiaries who underwent CAS from July 2009 to June 2011 at 927 US hospitals. Thirty-day risk-standardized mortality rates were calculated using the Hospital Compare statistical method, a well-validated hierarchical generalized linear model that included both patient-level and hospital-level predictors. Claims were examined from 22 708 patients undergoing CAS, with a crude 30-day mortality rate of 2.0%. Risk-standardized 30-day mortality rates after CAS varied from 1.1% to 5.1% (P<0.001 for the difference). Thirteen hospitals had risk-standardized mortality rates that were statistically (P<0.05) higher than the national mean. Conversely, 5 hospitals had risk-standardized mortality rates that were statistically (P<0.05) lower than the national mean.
  
  
  CONCLUSIONS
  We used administrative claims to identify several CAS hospitals with excessively high 30-day mortality after carotid stenting. When combined with information currently used by Medicare for CAS recertification, such as clinical registry data and program reports, clinical outcomes comparisons could enhance Medicare's ability to identify hospitals that are questionable candidates for recertification.
authors.affiliation: From the Department of Veterans Affairs' Center for Health Equity Research and Promotion, Philadelphia Veterans Affairs Medical Center, PA (A.J.E., P.W.G.); Division of General Internal Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia (A.J.E., L.Y., F.Y., P.W.G.); and Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia (A.J.E., P.W.G.).
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Epstein
authors.affiliation: From the Department of Veterans Affairs' Center for Health Equity Research and Promotion, Philadelphia Veterans Affairs Medical Center, PA (A.J.E., P.W.G.); Division of General Internal Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia (A.J.E., L.Y., F.Y., P.W.G.); and Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia (A.J.E., P.W.G.).
authors.forename: Lin
authors.initials: L
authors.lastname: Yang
authors.affiliation: From the Department of Veterans Affairs' Center for Health Equity Research and Promotion, Philadelphia Veterans Affairs Medical Center, PA (A.J.E., P.W.G.); Division of General Internal Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia (A.J.E., L.Y., F.Y., P.W.G.); and Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia (A.J.E., P.W.G.).
authors.forename: Feifei
authors.initials: F
authors.lastname: Yang
authors.affiliation: From the Department of Veterans Affairs' Center for Health Equity Research and Promotion, Philadelphia Veterans Affairs Medical Center, PA (A.J.E., P.W.G.); Division of General Internal Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia (A.J.E., L.Y., F.Y., P.W.G.); and Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia (A.J.E., P.W.G.). petergro@upenn.edu.
authors.forename: Peter W
authors.initials: PW
authors.lastname: Groeneveld
mesh_terms: D000368:Aged; D017536:Carotid Artery, Common / Q000601:surgery*; D016893:Carotid Stenosis / Q000401:mortality / Q000601:surgery*; D016894:Endarterectomy, Carotid / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D017052:Hospital Mortality / Q000639:trends; D006761:Hospitals; D006801:Humans; D008297:Male; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D015607:Stents; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology
keywords: Medicare; outcome assessment (health care)