title: Analysis of administrative data finds endoscopist quality measures associated with postcolonoscopy colorectal cancer.
abstract: OBJECTIVE
  Most quality indicators for colonoscopy measure processes; little is known about their relationship to patient outcomes. We investigated whether characteristics of endoscopists, determined from administrative data, are associated with development of postcolonoscopy colorectal cancer (PCCRC).
  
  
  METHODS
  We identified individuals diagnosed with colorectal cancer in Ontario from 2000 to 2005 using the Ontario Cancer Registry. We determined performance of colonoscopy using Ontario Health Insurance Plan data. Patients who had complete colonoscopies 7 to 36 months before diagnosis were defined as having a PCCRC. Patients who had complete colonoscopies within 6 months of diagnosis had detected cancers. We determined if endoscopist factors (volume, polypectomy and completion rate, specialization, and setting) were associated with PCCRC using logistic regression, controlling for potential covariates.
  
  
  RESULTS
  In the study, 14,064 patients had a colonoscopy examination within 36 months of diagnosis; 584 (6.8%) with distal and 676 (12.4%) with proximal tumors had PCCRC. The endoscopist's specialty (nongastroenterologist/nongeneral surgeon) and setting (non-hospital-based colonoscopy) were associated with PCCRC. Those who underwent colonoscopy by an endoscopist with a high completion rate were less likely to have a PCCRC (distal: odds ratio [OR], 0.73; 95% confidence interval [CI], 0.54-0.97; P = .03; proximal: OR, 0.72; 95% CI, 0.53-0.97; P = .002). Patients with proximal cancers undergoing colonoscopy by endoscopists who performed polypectomies at high rates had a lower risk of PCCRC (OR, 0.61; 95% CI, 0.42-0.89; P < .0001). Endoscopist volume was not associated with PCCRC.
  
  
  CONCLUSIONS
  Endoscopist characteristics derived from administrative data are associated with development of PCCRC and have potential use as quality indicators.
authors.affiliation: Department of Surgery and Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada. baxtern@smh.toronto.on.ca
authors.forename: Nancy N
authors.initials: NN
authors.lastname: Baxter
authors.forename: Rinku
authors.initials: R
authors.lastname: Sutradhar
authors.forename: Shawn S
authors.initials: SS
authors.lastname: Forbes
authors.forename: Lawrence F
authors.initials: LF
authors.lastname: Paszat
authors.forename: Refik
authors.initials: R
authors.lastname: Saskin
authors.forename: Linda
authors.initials: L
authors.lastname: Rabeneck
mesh_terms: D000236:Adenoma / Q000175:diagnosis*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002983:Clinical Competence; D003113:Colonoscopy / Q000193:education*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D055088:Early Detection of Cancer / Q000592:standards*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario; D011786:Quality Control; D055815:Young Adult