title: Prospective evaluation of screening colonoscopy: who is being screened?
abstract: BACKGROUND
  Universal access to medical procedures is deemed an advantage of the Canadian health care system. The purposes of this prospective study were to determine the degree to which the practice of colon cancer screening by colonoscopy differed among socioeconomic classes and to assess adherence to screening guidelines.
  
  
  METHODS
  Consecutive patients scheduled to undergo colonoscopy at a single center between August 2000 and August 2002 completed a questionnaire that determined patient characteristics and indications for the procedure. The patients were divided into two groups: screening patients, defined as individuals who indicated they were undergoing colonoscopy for screening purposes and were asymptomatic, and a control group, which comprised patients undergoing colonoscopy because of symptoms. Statistical analysis was performed to determine if patients in the screening group had different characteristics with respect to socioeconomic class, compared with the control group.
  
  
  RESULTS
  A total of 1088 patients completed the questionnaire: 707 (65%) had colonoscopy because of symptoms, compared with 381 (35%) who underwent a screening examination. Mean age and marital status were similar in both groups. Of all colonoscopy procedures, there was a significantly greater proportion of men undergoing colonoscopy for screening purposes: 199 (52.2%) vs. 294 (41.6%) in the symptomatic group ( p = 0.001). Based on the Cochran-Armitage test, patients in the screening group had significantly higher education levels ( p = 0.004) and household incomes ( p = 0.001).
  
  
  CONCLUSIONS
  Income and education level, two indices of socioeconomic status, are statistically significantly higher in patients undergoing screening colonoscopy compared with those having colonoscopy for any other reason.
authors.affiliation: Division of Gastroenterology, Department of Medicine, St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Brian
authors.initials: B
authors.lastname: Bressler
authors.forename: Charles
authors.initials: C
authors.lastname: Lo
authors.forename: Jack
authors.initials: J
authors.lastname: Amar
authors.forename: Scott
authors.initials: S
authors.lastname: Whittaker
authors.forename: Hugh
authors.initials: H
authors.lastname: Chaun
authors.forename: Lawrence
authors.initials: L
authors.lastname: Halparin
authors.forename: Robert
authors.initials: R
authors.lastname: Enns
mesh_terms: D018253:Adenoma, Villous / Q000175:diagnosis* / Q000453:epidemiology; D018256:Adenomatous Polyps / Q000175:diagnosis* / Q000453:epidemiology; D000328:Adult; D000368:Aged; D002170:Canada / Q000453:epidemiology; D003111:Colonic Polyps / Q000175:diagnosis* / Q000453:epidemiology; D003113:Colonoscopy / Q000706:statistics & numerical data*; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D004522:Educational Status; D005260:Female; D019983:Guideline Adherence / Q000706:statistics & numerical data; D006801:Humans; D007182:Income; D008297:Male; D008403:Mass Screening / Q000706:statistics & numerical data*; D008875:Middle Aged; D009313:National Health Programs / Q000706:statistics & numerical data; D011446:Prospective Studies; D012959:Socioeconomic Factors; D014600:Utilization Review / Q000706:statistics & numerical data