Reasons for Participation and Nonparticipation in Colorectal Cancer Screening: A Randomized Trial of Colonoscopy and CT Colonography

Abstract

We compared reported reasons for participation and nonparticipation in colorectal cancer (CRC) screening between colonoscopy and computed tomographic (CT) colonography in a randomized controlled trial. We randomly invited 8,844 people for screening by colonoscopy or CT colonography. On a questionnaire, invitees indicated reasons for participation or nonparticipation and indicated the most decisive reason. The most frequently cited reasons to accept screening were early detection of precursor lesions and CRC, and contribution to science. The most frequently cited reasons to decline were the unpleasantness of the examination, the inconvenience of the preparation, a lack of symptoms, and "no time/too much effort." Among colonoscopy nonparticipants, elderly invitees cited inconvenience less often, and absence of symptoms more often, than did the group overall. The reason reported most frequently as the most decisive reason not to participate was the unpleasantness of the examination among colonoscopy nonparticipants, and "no time/too much effort" and lack of symptoms among CT colonography nonparticipants. In light of these results, future screening programs could tailor the information provided to invitees.