GSTM1 and colorectal carcinoma: Interestingly, a recent Finnish study found that a f-Hb concentration threshold of ≥25 μg Hb/g faeces for women and ≥70 μg Hb/g faeces for men resulted in similar CRC detection rates (0.16% in women and 0.18% in men) and almost identical PPV for CRC (6.4% and 6.6%).26