What is FIT?
The Faecal Immunochemical Test (FIT) is a dipstick test for stool.
It detects and measures minute quantities of blood in the stool-- to the nearest microgram.
Bowel cancer can release blood from the bowels into stool. FIT measures the levels of blood in the stool known as faecal haemoglobin (FHb). FHb is expected to be higher if bowel cancer is present. A negative FIT (no blood in stool) could rule out cancer.
What is the NICE FIT study?
The NICE FIT study is the largest study in England investigating whether FIT can be used to rule out bowel cancer instead of a colonoscopy. We aim to test a minimum of 5500 patients in London, and further patients across the UK to create a robust evidence base that patients, GPs and hospital doctors can use with confidence.
Why are we doing this research?
Evidence from studies conducted around the world has suggested that FIT could rule out bowel cancer in symptomatic patients. This could avoid the need for a colonoscopy in patients being investigated with bowel symptoms. Consequently, FIT has been launched in several parts of the UK, and is being readied for usage in London.
However, we do not know whether this evidence holds true in England, where only one large research study on FIT has been published. As FHb levels vary by age, sex, ethnicity and deprivation, large scale diagnostic studies are required to create reference values for our population. This view was endorsed by a Health Technology Assessment commissioned by the NIHR.