15-Year Benefits of Sigmoidoscopy Screening on Colorectal Cancer Incidence and Mortality.

Because screening was used by only 58% to 84% of participants in the 4 trials, even substantially higher reduction of incidence would be expected for those participants who actually accepted the screening offer, in line with results from observational studies ([5]). [PMID: 30261804] doi:10.1177/0969141318790775 5 Brenner H, Stock C, Hoffmeister M. Effect of screening sigmoidoscopy and screening colonoscopy on colorectal cancer incidence and mortality: systematic review and meta-analysis of randomised controlled trials and observational studies. Focusing on these cases - most of which are likely truly incident cases - would yield an estimated incidence reduction of approximately 30% for any CRC and 50% for distal CRC, which is much higher than the reported 21% and 32% reduction of CRC detection from the time of recruitment. [Extracted from the article]