Diagnostic accuracy of quantitative faecal immunochemical test in symptomatic patients for the investigation of colorectal cancer once accounting for anaemia severity and iron deficiency

The diagnostic accuracy of FIT is excellent regardless of the severity of anaemia, iron deficiency, symptom type or demographics. The FIT cut-off can be increased safely to 20 μg Hb/g irrespective of anaemia severity or iron deficiency. Altering the definition of IDA does not pragmatically increase the detection of CRC in negative/low FIT patients.