What were the aims of the ASCEND study?

In the UK, over 40,000 people receive a diagnosis of bowel cancer every year, and over 16,000 die from the disease. Studies suggest that screening the general population can help identify cancer at an earlier stage, when treatment is much more likely to be successful.

The English NHS Bowel Cancer Screening Programme was started in 2006 and aims to reduce the number of people dying from bowel cancer. Every two years, people aged between 60–74 years old are sent a test to look for hidden blood in the stool, which can sometimes be a sign of bowel cancer. This test is called a faecal occult blood test or FOBt. The test is completed at home and then returned in a prepaid envelope to a screening centre for analysis. It has been estimated that the risk of dying from bowel cancer is reduced, by about 25%, in those who regularly participate in FOBt screening, but not everyone takes part in screening when invited.

Findings from the NHS Bowel Cancer Screening Programme suggest that people living in more deprived areas are less likely to participate in the screening programme. This is concerning because these people are also more likely to die from bowel cancer. The decisions people make when it comes to screening participation are likely to be influenced by the way in which they are invited, and the information they receive with their invitation. The ASCEND study tested four different invitation/information strategies in the NHS Bowel Cancer Screening Programme to see if any could increase the numbers of people in more deprived areas participating in screening, without compromising already much higher participation in other areas.