“…Research has explored many basic aspects concerning f-Hb and it has been shown that f-Hb rises with age and is higher in men than in women (7,8), and higher in the more socioeconomically deprived (8,9). It has been well documented that higher f-Hb is associated with a higher incidence of CRC and advanced adenoma, that is, advanced neoplasia (AN), because f-Hb is directly related to the severity of colorectal disease (10). Thus, it is hardly surprising that, if FITs are used as a simple qualitative dichotomous investigation with a single cut-off f-Hb applied to all participants, as is done in almost all current CRC screening programmes, as the f-Hb cut-off applied is increased, positivity rate, AN detection rate and sensitivity decrease, while specificity, positive predictive value and interval cancer proportion increase.…”