Objectives To identify the reasons why some people do not participate in bowel cancer screening so that steps can be taken to improve informed decision-making.

Design Qualitative study, using focus groups with thematic analysis of data to identify, analyse and report patterns. Transcripts were repeatedly read and inductively coded using a phenomenological perspective, and organised into key themes.

Setting Belfast and Armagh, two areas of Northern Ireland with relatively low uptake of bowel cancer screening.

Participants Ten women and 18 men in three single-gender focus groups (two male and one female), each with 9–10 participants. Study participants were recruited by convenience sampling from the general public and were eligible for, but had not taken part in, the Northern Ireland Bowel Cancer Screening Programme.

Results Key themes identified were fear of cancer; the test procedure; social norms; past experience of cancer and screening; lack of knowledge or understanding about bowel cancer screening; and resulting behaviour towards the test. Fear about receiving bad news and reluctance to conduct the test themselves were reactions that participants seemed willing to overcome after taking part in open discussion about the test.

Conclusions We identified barriers to participation in bowel cancer screening and used these insights to develop new materials to support delivery of the programme. Some of the issues raised have been identified in other UK settings, suggesting that knowledge about barriers, and strategies to improve uptake, may be generalisable.