The FOB and FIT tests can detect tiny amounts of blood in your poo. They are used for bowel screening. You will get a home screening kit when you reach the age that bowel cancer screening starts in your country.
The main difference between FOB and FIT tests are the number of samples you need to take.
- FOB test
For the FOB test, you need to take three different poo samples, each on different days.
- FIT test
For the FIT test, you only need to take one sample.
The test kit comes with a set of instructions. Before you take a sample, it is helpful to:
- read through all the instructions
- get everything you need ready
- write any details on the test kit, for example the date.
You return the samples to the test centre in a pre-paid envelope. If you have any questions about the sample collection, or have a disability that makes using the kit difficult, call your country’s screening helpline. If you need a new test kit, they can send you one. These are the helpline numbers:
- In England, call 0800 707 6060, Monday to Friday, 9am to 5pm.
- In Scotland, call 0800 0121 833, Monday to Friday, 8am to 5pm.
- In Wales, call 0800 294 3370, Monday to Friday, 8am to 5pm.
- In Northern Ireland, call 0800 015 2514, Monday to Friday, 9am to 5pm.
If you live in England, you have 14 days to return the test card after taking the first sample.
In the rest of the UK, you have 10 days to return the test card after taking the first sample. You will get a reminder after about 4 weeks if you do not return the test kit.
If you decide not to take part in the screening programme, you can choose not to respond. Or you can contact your country’s helpline to say you will not be sending your kit back.
You should get a letter with the results of your home screening test within 2 weeks. Your GP will also get a letter.
With the FOB test, there are three possible test results:
The FIT test gives only a normal or abnormal test result.
Sometimes you may be asked to repeat the test. This may be because of:
- a technical failure — there was a problem when your samples were tested in the laboratory.
- a spoilt kit — the test kit cannot be tested in the laboratory, because it has not been used properly or has been damaged.
Around 98 out of 100 people (about 98%) have a normal result. This means no blood was found.
2 years after your test, you will be sent another test kit if you are still within the age range.
If you have any symptoms before your next screening test, it is important to go to see your GP. Do not wait for your next test kit.
About 2 in 100 people (around 2%) have an abnormal result. If you have this result, it means blood was found in your test. Blood in your test result does not mean you have bowel cancer.
Only about 1 in 10 people with an abnormal result (about 10%) have cancer. Blood in poo can be caused by other conditions such as polyps or piles (haemorrhoids).
If you have an abnormal result, you will be offered an assessment and probably a bowel test called a colonoscopy.
A small number of people may have an unclear result. This means there was some blood detected, but not enough to give an abnormal result.
Having an unclear result does not mean you have bowel cancer. It just means you need to do a second test to check for blood in your poo. You will be sent another home screening kit.
Most people who do the second test get a normal result. If the result of your second test is normal, you may be sent another kit to confirm the result.
If the result of the second test is unclear or abnormal, you will usually be offered a colonoscopy.