Faecal occult blood tests (FOBT)

Thanks to the National Bowel Cancer Screening Program, people aged 50 to 74 receive a free FOBT in the mail every two years.

What's an FOBT?

A faecal occult blood test (FOBT) is a simple test that looks for the early signs of bowel cancer. It can be done in the privacy of your own home and involves taking a minuscule sample from two separate bowel motions (faeces) using a test kit. Samples are then sent to a laboratory for testing.

FOBTs look for tiny amounts of blood (that often can't be seen by the naked eye) in bowel motions. Blood is usually caused by something less serious than cancer. However, it may be a sign of an early bowel cancer or a polyp: a growth on the inside of the bowel that could develop into cancer. If the FOBT finds blood, more tests are done to find out what's caused the bleeding.

How should an FOBT be safely stored?

Keep the sample in a cool, dry place, preferably 2–10 degrees, or in the fridge, away from food, until the second sample is taken and until you can post the envelope. Avoid posting the envelope if it's a very hot day, post it in an indoor mail box, or post it close to mail collection times.

Who needs an FOBT?

Men and women aged 50 and over, without symptoms and without a strong family history of bowel cancer, are encouraged to do an FOBT every two years. Those with a strong family history of bowel cancer or any symptoms should see a doctor.

How can I get an FOBT?

The National Bowel Cancer Screening Program sends free test kits to people aged 50 to 74 every two years.

Why two samples?

Having two samples instead of one means any problem is more likely to be found. The samples need to be taken from two separate bowel motions. It's best if the samples are completed as close to each other as possible, and certainly within 10 days. They should be posted to the laboratory as soon as both samples are completed.

How accurate are FOBTs?

Although no screening test is 100 per cent accurate, the FOBT is currently the most widely available and well trialled screening test for bowel cancer. If you do an FOBT every two years, you can reduce your risk of dying from bowel cancer by up to a third.

What do the results mean?

Negative (no blood found)

A negative FOBT doesn't mean that you don't have, or can never develop, bowel cancer. This is because some bowel cancers may not bleed, or may only bleed every now and then. If you receive a negative FOBT result, it's recommended that you continue to have an FOBT every two years.

It's also recommended that you see your doctor if you notice any sign of blood in your bowel motions or have any symptoms of bowel cancer, even if your last screening test was normal.

Positive (blood found)

There could be several reasons for finding blood in a bowel motion that may not be related to bowel cancer, for example, bleeding from piles, menstrual blood, etc.

However, if blood is found, it's important to speak to your doctor. Your doctor will talk with you about follow-up tests (such as colonoscopies) which check for bowel cancer, polyps or other causes of the positive FOBT result.

Remember, bowel cancer is 90 per cent curable if found at an early stage.


A colonoscopy is a test that allows a specialist to look at the inside of the bowel. It's a day procedure. The test itself takes 20 to 30 minutes and is usually done in a hospital or day clinic.

The day before the colonoscopy you'll be asked to drink a special preparation to help empty the bowel. On the day of the procedure you may be given medicine that makes you feel drowsy, so it's important that you don't drive home after the test.

The specialist will insert a narrow, flexible tube called a colonoscope into your back passage. The colonoscope allows the specialist to look for polyps or bowel cancers. Most polyps can be removed during the colonoscopy.

If you need to have a colonoscopy your doctor will explain the procedure and tell you about any risks. It's rare for a colonoscopy to cause serious problems.

Public hospital patients often have to wait several weeks, or sometimes months for the procedure. Private patients usually have a shorter wait.

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