title: Randomized trial of different screening strategies for colorectal cancer: patient response and detection rates.
abstract: BACKGROUND
  Although there is general consensus concerning the efficacy of colorectal cancer screening, there is a lack of agreement about which routine screening strategy should be adopted. We compared the participation and detection rates achievable through different strategies of colorectal cancer screening.
  
  
  METHODS
  From November 1999 through June 2001 we conducted a multicenter, randomized trial in Italy among a sample of 55-64 year olds in the general population who had an average risk of colorectal cancer. People with previous colorectal cancer, adenomas, inflammatory bowel disease, a recent (< or =2 years) colorectal endoscopy or fecal occult blood test (FOBT), or two first-degree relatives with colorectal cancer were excluded. Eligible subjects were randomly assigned, within the roster of their general practitioner, to 1) biennial FOBT (delivered by mail), 2) biennial FOBT (delivered by general practitioner or a screening facility), 3) patient's choice of FOBT or "once-only" sigmoidoscopy, 4) "once-only" sigmoidoscopy, or 5) sigmoidoscopy followed by biennial FOBT. An immunologic FOBT was used. Participation and detection rates of the strategies tested were compared using multivariable logistic regression models that adjusted for age, sex, and screening center. All statistical tests were two-sided.
  
  
  RESULTS
  Of 28 319 people sampled, 1637 were excluded and 26 682 were randomly assigned to a screening arm. After excluding undelivered letters (n = 427), the participation rates for groups 1, 2, 3, 4, and 5 were 30.1% (682/2266), 28.1% (1654/5893), 27.1% (970/3579), 28.1% (1026/3650), and 28.1% (3049/10 867), respectively. Of the 2858 subjects screened by FOBT, 122 (4.3%) had a positive test result, 10 (3.5 per 1000) had colorectal cancer, and 39 (1.4%) had an advanced adenoma. Among the 4466 subjects screened by sigmoidoscopy, 341 (7.6%) were referred for colonoscopy, 18 (4 per 1000) had colorectal cancer, and 229 (5.1%) harbored an advanced adenoma.
  
  
  CONCLUSIONS
  The participation rates were similar for sigmoidoscopy and FOBT. The detection rate for advanced neoplasia was three times higher following screening by sigmoidoscopy than by FOBT.
authors.affiliation: Centro Prevenzione Oncologica Regione Piemonte and Azienda Sanitaria Ospedaliera S Giovanni Battista, Torino, Italy. nereo.segnan@cpo.it
authors.forename: Nereo
authors.initials: N
authors.lastname: Segnan
authors.forename: Carlo
authors.initials: C
authors.lastname: Senore
authors.forename: Bruno
authors.initials: B
authors.lastname: Andreoni
authors.forename: Arrigo
authors.initials: A
authors.lastname: Arrigoni
authors.forename: Luigi
authors.initials: L
authors.lastname: Bisanti
authors.forename: Alessandro
authors.initials: A
authors.lastname: Cardelli
authors.forename: Guido
authors.initials: G
authors.lastname: Castiglione
authors.forename: Cristiano
authors.initials: C
authors.lastname: Crosta
authors.forename: Roberta
authors.initials: R
authors.lastname: DiPlacido
authors.forename: Arnaldo
authors.initials: A
authors.lastname: Ferrari
authors.forename: Roberto
authors.initials: R
authors.lastname: Ferraris
authors.forename: Franco
authors.initials: F
authors.lastname: Ferrero
authors.forename: Mario
authors.initials: M
authors.lastname: Fracchia
authors.forename: Stefano
authors.initials: S
authors.lastname: Gasperoni
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Malfitana
authors.forename: Serafino
authors.initials: S
authors.lastname: Recchia
authors.forename: Mauro
authors.initials: M
authors.lastname: Risio
authors.forename: Mario
authors.initials: M
authors.lastname: Rizzetto
authors.forename: Giorgio
authors.initials: G
authors.lastname: Saracco
authors.forename: Mauro
authors.initials: M
authors.lastname: Spandre
authors.forename: Delio
authors.initials: D
authors.lastname: Turco
authors.forename: Patricia
authors.initials: P
authors.lastname: Turco
authors.forename: Marco
authors.initials: M
authors.lastname: Zappa
mesh_terms: D003111:Colonic Polyps / Q000175:diagnosis / Q000517:prevention & control; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology / Q000517:prevention & control*; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009780:Occult Blood; D016017:Odds Ratio; D010342:Patient Acceptance of Health Care; D011177:Postal Service / Q000706:statistics & numerical data; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012812:Sigmoidoscopy; D011795:Surveys and Questionnaires