The fetal immunochemical test (FIT) is a non-invasive preliminary screening tool to detect blood in the stool as a part of lower gastrointestinal (GI) bleeding. The test involves examining small stool samples for the presence of human haemoglobin using immunological methods. The test is recommended by healthcare providers for colorectal cancer screening, to locate gastrointestinal bleeding sites, identify individuals at risk, and facilitate further diagnosis and interventions.