Impact of screening programme using the faecal immunochemical test on stage of colorectal cancer: Results from the IMPATTO study

To evaluate the impact of faecal immunochemical test (FIT) screening on stage distribution at diagnosis, and to estimate relative incidence rates by stage in screened at first and subsequent rounds vs. unscreened. We included all incident cases occurring in 2000-2008 in 50- to 71-year-olds residing in areas with an FIT-screening programme. Multinomial logistic models were computed to estimate the relative risk ratio (RRR) of stages I and IV, compared to stage II + III, adjusting for age, sex, geographical area, and incidence year. Proportions were then used to estimate incidence rate ratios (IRR) by stage for screened subjects at the first and at subsequent rounds vs. unscreened subjects, a…