title: Surgeon specific mortality in adult cardiac surgery: comparison between crude and risk stratified data.
abstract: OBJECTIVE
  As a result of recent failures in clinical governance the government has made a commitment to bring individual surgeons' mortality data into the public domain. We have analysed a database to compare crude mortality after coronary artery bypass surgery with outcomes that were stratified by risk.
  
  
  METHODS
  Retrospective analysis of prospectively collected data.
  
  
  METHODS
  All NHS centres in the geographical north west of England that undertake cardiac surgery in adults.
  
  
  METHODS
  All patients undergoing isolated bypass graft surgery for the first time between April 1999 and March 2002.
  
  
  METHODS
  Surgeon specific postoperative mortality and predicted mortality by EuroSCORE.
  
  
  RESULTS
  8572 patients were operated on by 23 surgeons. Overall mortality was 1.7%. Observed mortality between surgeons ranged from 0% to 3.7%; predicted mortality ranged from 2% to 3.7%. Eighty five per cent (7286) of the patients had a EuroSCORE of 5 or less; 49% of the deaths were in this lower risk group. A large proportion of the variability in predicted mortality between surgeons was due to a small but differing number of high risk patients.
  
  
  CONCLUSIONS
  It is possible to collect risk stratified data on all patients undergoing coronary bypass surgery. For most the predicted mortality is low. The small proportion of high risk patients is responsible for most of the differences in predicted mortality between surgeons. Crude comparisons of death rates can be misleading and may encourage surgeons to practise risk averse behaviour. We recommend a comparison of death rates that is stratified by risk and based on low risk cases as the national benchmark for assessing consultant specific performance.
authors.affiliation: South Manchester University Hospital, Manchester M23 9LT. ben.bridgewater@smuht.nwest.nhs.uk
authors.forename: Ben
authors.initials: B
authors.lastname: Bridgewater
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Grayson
authors.forename: Mark
authors.initials: M
authors.lastname: Jackson
authors.forename: Nicholas
authors.initials: N
authors.lastname: Brooks
authors.forename: Geir J
authors.initials: GJ
authors.lastname: Grotte
authors.forename: Daniel J M
authors.initials: DJ
authors.lastname: Keenan
authors.forename: Russell
authors.initials: R
authors.lastname: Millner
authors.forename: Brian M
authors.initials: BM
authors.lastname: Fabri
authors.forename: Mark
authors.initials: M
authors.lastname: Jones
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003253:Consultants; D001026:Coronary Artery Bypass / Q000401:mortality* / Q000592:standards; D004739:England / Q000453:epidemiology; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008485:Medical Audit; D008505:Medical Staff, Hospital / Q000706:statistics & numerical data*; D008875:Middle Aged; D011182:Postoperative Care / Q000401:mortality; D011446:Prospective Studies; D013902:Radiography, Thoracic / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors