title: Learning the hard way: the importance of accurate data.
abstract: OBJECTIVE
  The outcome of surgery for colorectal cancer in each unit in the UK is collated by the National Bowel Cancer Audit Project (NBOCAP). In 2008-2009 our unit had a raw 30-day postoperative mortality close to the national average, but when it was nationally adjusted it appeared to be an outlier. The purpose of this study was to identify reasons for this disparity.
  
  
  METHODS
  All records were obtained for patients undergoing surgery for colorectal cancer over the 2 years. Data submitted to NBOCAP to determine adjusted rates were compared with actual data.
  
  
  RESULTS
  There were major discordances between submitted and actual data for American Society of Anesthesiology grades and timing of surgery. This explained why the unit appeared to be an outlier.
  
  
  CONCLUSIONS
  There is increasing emphasis on outcome of health service delivery, which has important implications. Submission of correct data is essential if objective comparison is to be made on which to base decisions on service delivery among units and within health regions.
authors.affiliation: Academic Department of Medical and Surgical Gastroenterology and Intensive Care, Homerton University Hospital NHS Foundation Trust, London, UK.
authors.forename: R S
authors.initials: RS
authors.lastname: Lewis
authors.forename: D G
authors.initials: DG
authors.lastname: Graham
authors.forename: J D
authors.initials: JD
authors.lastname: Watson
authors.forename: P J
authors.initials: PJ
authors.lastname: Lunniss
mesh_terms: D015179:Colorectal Neoplasms / Q000401:mortality* / Q000601:surgery*; D017052:Hospital Mortality; D006801:Humans; D010043:Outcome and Process Assessment, Health Care; D006113:United Kingdom / Q000453:epidemiology