The impact of population-based faecal occult blood test screening on colorectal cancer mortality: a matched cohort study.
BACKGROUND
Randomised trials show reduced colorectal cancer (CRC) mortality with faecal occult blood testing (FOBT). This outcome is now examined in a routine, population-based, screening programme.


METHODS
Three biennial rounds of the UK CRC screening pilot were completed in Scotland (2000-2007) before the roll out of a national programme. All residents (50-69 years) in the three pilot Health Boards were invited for screening. They received a FOBT test by post to complete at home and return for analysis. Positive tests were followed up with colonoscopy. Controls, selected from non-pilot Health Boards, were matched by age, gender, and deprivation and assigned the invitation date of matched invitee. Follow-up was from invitation date to 31 December 2009 or date of death if earlier.


RESULTS
There were 379 655 people in each group (median age 55.6 years, 51.6% male). Participation was 60.6%. There were 961 (0.25%) CRC deaths in invitees, 1056 (0.28%) in controls, rate ratio (RR) 0.90 (95% confidence interval (CI) 0.83-0.99) overall and 0.73 (95% CI 0.65-0.82) for participants. Non-participants had increased CRC mortality compared with controls, RR 1.21 (95% CI 1.06-1.38).


CONCLUSIONS
There was a 10% relative reduction in CRC mortality in a routine screening programme, rising to 27% in participants.
Scottish Bowel Screening Research Unit, Kings Cross, Clepington Road, Dundee DD3 8EA, UK. g.libby@dundee.ac.uk
G
G
Libby
D H
DH
Brewster
P L
PL
McClements
F A
FA
Carey
R J
RJ
Black
J
J
Birrell
C G
CG
Fraser
R J C
RJ
Steele
D000368:Aged; D015331:Cohort Studies; D003113:Colonoscopy / Q000379:methods; D015179:Colorectal Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000401:mortality* / Q000517:prevention & control; D016001:Confidence Intervals; D005243:Feces / Q000737:chemistry*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D009780:Occult Blood; D010865:Pilot Projects; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D012606:Scotland / Q000453:epidemiology; D012923:Social Class