title: Patient factors influencing the completion rate in colonoscopy.
abstract: BACKGROUND
  Since its introduction in the late 1960s, the technology of colonoscopy has developed rapidly, and the competence of the endoscopists has increased. Still, a complete colonoscopy is not always possible to perform.
  
  
  OBJECTIVE
  To assess, in a population-based setting, which patient factors influence the success rate.
  
  
  METHODS
  All colonoscopy records during 1979-1995 in one Swedish county (population 258,000) were retrieved. Information was obtained about each patient's sex and age, date of examination, the endoscopist and indications for colonoscopy, findings, type of colonoscopy and reasons for an incomplete colonoscopy. Results were assessed by univariate and multivariate analyses.
  
  
  RESULTS
  Of 5145 colonoscopies, 4153 (81%) were complete. Completion rates were influenced by (odds ratio for completion [95% confidence intervals]): sex, male versus female (2.00 [1.39-2.86]); age, youngest quartile versus oldest quartile (1.49 [1.04-2.13]); indication for colonoscopy, previous colonic surgery or long-standing colitis versus other indications (2.08 [1.23-3.45]); and diverticulosis, presence versus no presence (0.79 [0.62-0.99]). The time period (proxy variable for the development of endoscopes) had no impact on completion rates.
  
  
  CONCLUSIONS
  The completion rate was lower than that has been reported from previous hospital-based studies. Lower completion rates were found in women, older patients and in patients with diverticulosis. Higher completion rates were noted in patients with previous colonic surgery and long-standing colitis. The completion rates were not influenced by the development of the endoscopes.
authors.affiliation: Department of Surgery, University Hospital, SE-75185 Uppsala, Sweden. george.dafnis@telia.com
authors.forename: G
authors.initials: G
authors.lastname: Dafnis
authors.forename: F
authors.initials: F
authors.lastname: Granath
authors.forename: L
authors.initials: L
authors.lastname: Påhlman
authors.forename: A
authors.initials: A
authors.lastname: Ekbom
authors.forename: P
authors.initials: P
authors.lastname: Blomqvist
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D016009:Chi-Square Distribution; D003092:Colitis / Q000175:diagnosis; D003113:Colonoscopy / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D013272:Stomach Diseases / Q000175:diagnosis