title: Demonstrating safety through in-hospital mortality analysis following elective abdominal aortic aneurysm repair in England.
abstract: BACKGROUND
  The aims were to assess the evidence that individual hospitals had mortality rates in excess of the national average after abdominal aortic aneurysm (AAA) repair and to develop an effective method for monitoring mortality using local data.
  
  
  METHODS
  Hospital Episode Statistics identified patients undergoing elective infrarenal AAA repair. A technique was developed that compared individual hospital mortality rates with the mortality rate in the remainder of England. The strength of evidence that the death rate was less than elsewhere, and less than twice elsewhere, was quantified using a test of statistical significance. A moving average chart technique was devised using local data for mortality monitoring and comparison to the national average.
  
  
  RESULTS
  For 30 hospitals, the mortality rate was significantly greater than elsewhere, and in three hospitals it was demonstrably greater than twice that in the remainder of England. The moving average chart appeared to provide a useful technique for local mortality monitoring.
  
  
  CONCLUSIONS
  Different mortality rates exist for AAA repair within England. Mortality can be monitored locally and compared with the national average.
authors.affiliation: St George's Vascular Institute, St George's Hospital, London, UK.
authors.forename: P J E
authors.initials: PJ
authors.lastname: Holt
authors.forename: J D
authors.initials: JD
authors.lastname: Poloniecki
authors.forename: I M
authors.initials: IM
authors.lastname: Loftus
authors.forename: M M
authors.initials: MM
authors.lastname: Thompson
mesh_terms: D017544:Aortic Aneurysm, Abdominal / Q000401:mortality / Q000601:surgery*; D004739:England / Q000453:epidemiology; D017052:Hospital Mortality; D006801:Humans; D012307:Risk Factors; D017751:Safety Management; D015996:Survival Rate