Participants with the highest f‐Hb concentrations (>40‐46.9 μg Hb/g feces) had an OR of 12.0 (95% CI 7.8‐17.6) for detection of interval CRC compared with participants with unmeasurable f‐Hb concentrations (Model 2; Table 3). Here, GSTM1 is linked to colorectal carcinoma.