We assessed screening strategies to ameliorate the increasing incidence of colorectal cancer (CRC) among those <50 years in Aotearoa New Zealand (ANZ). We analysed CRC incidence and mortality and estimated the cost-effectiveness of screening with: one-off flexible sigmoidoscopy (FS) at age 40 (FS40) and 45 (FS45); and faecal immunochemical testing (FIT) for with a sensitivity cut-off of 75ng Hb/ml buffer (FIT75) and FIT200.

CRC incidence and mortality varied across birth cohorts, reached a low point for those born in the 1960s, and rose again thereafter. FS40 and FS45 would prevent >50% of CRC deaths over 20 years, vs. approximately 13% for FIT75 or FIT200. FS45 was shown to be the most effective and cost-effective strategy.

Long-term benefit would accrue from the adoption of FS screening and, where needed, FS diagnosis. Establishment of an FS-training course for nurses and other healthcare personnel would expand the required service provision.

The authors have declared no competing interest.

https://tewhatuora.shinyapps.io/mortality-web-tool/

This study did not receive any funding

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