GSTM1 and colorectal carcinoma: This study also reported data indicating that FIT alone, at the f-Hb cut-off of 10 μg Hb/g faeces, could offer improved rule-out performance for CRC compared to the NICE 2-week wait referral criteria; the sensitivity estimate for FIT was 96.7% (95% CI 82.2– 99.9%), compared to 46.7% (28.3–65.7%) for the NICE criteria [29].