Before the test, you will be given information about how to empty your bowel. You will be given a laxative or enema to take at home, or you may have an enema given at the clinic. The test will be done with care for your modesty. You may be asked to undress and wear a hospital gown.

To begin with, you may be referred to the outpatients department for a rigid sigmoidoscopy. The rigid sigmoidoscope is a small metal or plastic tube, through which a type of torch can be threaded. Whilst you are lying down, it is gently inserted into your rectum. This allows the doctor or nurse to get a detailed view of the inside of your rectum. Sometimes a small sample of tissue (a biopsy) is taken for further examination. The test itself takes only a few minutes and might feel uncomfortable.

Alternatively, a thin, lighted telescopic instrument called a flexible sigmoidoscope may be used. You may have to attend a special clinic for this test.

The flexible tube is gently inserted through your back passage. This lets the doctor see pictures of the inner lining of your rectum and sigmoid colon on a video screen. This is the part of the colon where most bowel cancer occurs. Tissue samples can be taken with flexible biopsy forceps. They will be looked at under a microscope later.

During the test, air will be puffed through the sigmoidoscope. This inflates your bowel to give a clearer view of the lining of the colon. You may get stomach pains or cramps caused by the air pressure. The test takes 10 to 15 minutes. It is a safe procedure, with a very slight risk of bowel perforation. You will be given written information about the risks.

You should not need to be sedated and you will be able to go home, or return to work, immediately after the test.

You may get your results on the day of the examination. If a biopsy has been taken, or a polyp removed, you may be called back to the hospital to discuss the results, or you may go to your own GP's surgery for the results. These are usually available within one to two weeks.

If something abnormal is found, it will be necessary for you to have the rest of your colon examined. This is beyond the reach of the sigmoidoscope, so it will be done by a longer telescope (a colonoscope) or a special X-ray (barium enema).

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