title: Data validation in an economic evaluation of surgery for colon cancer.
abstract: OBJECTIVE
  This study aimed to validate the accuracy of data retrieved in a prospective multicenter trial, the purpose of which was an economic evaluation of two techniques of surgery for colon cancer.
  
  
  METHODS
  Within the Swedish contribution of the COLOR trial (Colon Cancer Open or Laparoscopic Resection), an economic evaluation of open versus laparoscopic surgical techniques was conducted. Data were collected by case record forms (CRF), patient diaries, and telephone surveys every 2 weeks. The study period was 12 weeks, and the perspective was societal. Data from the first consecutive forty patients to complete the health economic study protocol were validated. Retrieved data were compared with data from medical records and data from local social security offices for agreement.
  
  
  RESULTS
  Statistically significant differences were found for duration of anesthesia, length of surgery, number of outpatient consultations by doctors and district nurses, complication rate, and the use of central venous lines. No significant differences were observed concerning length of hospital stay, disposable instruments cost, and time off work, all of which heavily influence total costs.
  
  
  CONCLUSIONS
  The present method of data collection regarding resources used in this setting seems to produce accurate data for economic evaluation; however, relative to complication rates, the method did not retrieve accurate data.
authors.affiliation: Department of Surgery, Karolinska Institutet, Karolina Uinversity Hospital, Huddinge, Stockholm, Sweden. martin.janson@karolinska.se
authors.forename: Martin
authors.initials: M
authors.lastname: Janson
authors.forename: Per
authors.initials: P
authors.lastname: Carlsson
authors.forename: Eva
authors.initials: E
authors.lastname: Haglind
authors.forename: Bo
authors.initials: B
authors.lastname: Anderberg
mesh_terms: D003082:Colectomy / Q000009:adverse effects / Q000191:economics* / Q000379:methods; D003110:Colonic Neoplasms / Q000601:surgery*; D003362:Cost-Benefit Analysis / Q000379:methods* / Q000592:standards; D003625:Data Collection / Q000379:methods; D019538:Health Care Surveys; D006801:Humans; D010535:Laparoscopy / Q000191:economics; D008499:Medical Records; D017059:Models, Econometric; D015337:Multicenter Studies as Topic / Q000379:methods* / Q000592:standards; D012107:Research Design; D013548:Sweden; D013673:Technology Assessment, Biomedical / Q000191:economics* / Q000379:methods / Q000592:standards