Median faecal haemoglobin concentration (faecal haemoglobin (f-Hb), μg Hb/g faeces), percentage with faecal haemoglobin concentration >400 μg Hb/g faeces and p-value comparing women and men by gender, stage and site for participants with colorectal cancer. This evidence concerns the gene GSTM1 and colorectal cancer.