title: Participation in four rounds of a French colorectal cancer screening programme with guaiac faecal occult blood test: a population-based open cohort study.
abstract: OBJECTIVE
  Four randomized controlled trials have demonstrated the efficacy of screening using a guaiac faecal occult blood test (gFOBT) on colorectal cancer (CRC) mortality. Whether their results are transposable to the real world is unknown. This study aimed to assess the determinants of participation in the first four rounds of the CRC screening programme using a gFOBT implemented since 2003 in the Haut-Rhin (Alsace) part of the French national programme.
  
  
  METHODS
  We performed a population-based open cohort study of all residents aged 50-74, around 200,000 people. They were invited by mail to participate every other year. The gFOBT kits (Hemoccult II) were first provided by general practitioners, and then directly mailed to persons who failed to comply.
  
  
  RESULTS
  The uptake decreased significantly across all rounds, from 54.3% to 47.1% (p < 0.0001), mainly in people younger than 60. The proportion of people screened by general practitioners increased significantly from 77.0% in the first round to 84.2% in the fourth (p < 0.01). Overall, 61.3% of the invited population participated at least once, and 14.3% had completed all the four tests. The colonoscopy uptake was around 91%, among the highest ever reported.
  
  
  CONCLUSIONS
  Despite the involvement of general practitioners, the uptake and adherence to repeat testing are modest and deteriorate with time, so that the reduction in CRC mortality in reality will be significantly lower than that in the trials. The benefit-risk balance of the French programme is, at present, less favourable than that shown in the trials.
authors.affiliation: Consultant gastroenterologist, Association for colorectal cancer screening in Alsace, Colmar, France bernard.denis@ch-colmar.fr.
authors.forename: Bernard
authors.initials: B
authors.lastname: Denis
authors.affiliation: Medical coordinator, Association for colorectal cancer screening in Alsace, Colmar, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gendre
authors.affiliation: Director, Association for colorectal cancer screening in Alsace, Colmar, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Perrin
mesh_terms: D015331:Cohort Studies; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D055088:Early Detection of Cancer / Q000379:methods; D005260:Female; D005602:France; D006138:Guaiac; D006801:Humans; D007202:Indicators and Reagents; D008297:Male; D009780:Occult Blood
chemical_list: D007202:Indicators and Reagents; D006138:Guaiac
keywords: colonoscopy; colorectal neoplasms/diagnosis; early detection of cancer/methods; mass screening/methods; occult blood