title: Impact of a colonoscopic screening examination for colorectal cancer on later utilization of distal GI endoscopies.
abstract: BACKGROUND
  Colonoscopic screening for colorectal cancer is being implemented in an increasing number of countries. This might lead to a demand for colonoscopies that could outstrip supply.
  
  
  OBJECTIVE
  We wanted to investigate whether undergoing a colonoscopic examination for colorectal cancer would affect the utilization of later distal GI endoscopies for other indications than follow-up of the findings at the screening examination (usual-care endoscopies).
  
  
  METHODS
  Prospective case control study.
  
  
  METHODS
  In 1996, a screening group of 634 individuals, aged 63 to 72 years, randomly drawn from the official population registry, was invited to a "once only" colonoscopic screening examination for colorectal cancer. A total of 451 individuals (71%) attended. An age- and sex-matched control group of 634 individuals was enrolled from the same registry. Both groups belonged to the encatchment area of a single hospital.
  
  
  METHODS
  Distal endoscopies performed in the 2 groups from January 1996 to November 2004 were registered by investigating medical records.
  
  
  RESULTS
  A total of 1268 individuals (52.4% women) were followed for 9 years. Sixty-three individuals (9.9%) in the screening group and 110 (17.4%) individuals in the control group (odds ratio 0.53, 95% confidence interval 0.38-0.73) had had a total of 85 and 169 usual-care distal endoscopies, respectively (P < .001).
  
  
  CONCLUSIONS
  Undergoing a colonoscopic examination for colorectal cancer seems to reduce the utilization of later usual-care endoscopic examinations. This finding could have an impact on the estimation of endoscopic resources needed for colorectal cancer screening.
authors.affiliation: Department of Medicine, Division of Gastroenterology, Rikshospitalet University Hospital, Oslo, Norway.
authors.forename: Espen
authors.initials: E
authors.lastname: Thiis-Evensen
authors.forename: Birgitte
authors.initials: B
authors.lastname: Seip
authors.forename: Morten H
authors.initials: MH
authors.lastname: Vatn
authors.forename: Geir S
authors.initials: GS
authors.lastname: Hoff
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D016099:Endoscopy, Gastrointestinal / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors