Intended and Actual Participation in the Colorectal Cancer Screening Program.

Background: The public generally has a positive view of colorectal cancer screening, but there is still room for improvement in participation rates. The aim of this study was to identify factors that are associated with intended and actual participation.

Methods: We conducted a prospective cohort study of a random sample of insurees of the AOK (a statutory health insurance carrier) in the German federal state of Lower Saxony. 50-year-old men and 55-year-old women who were eligible for their first screening colonoscopy received a written questionnaire in June 2020, three weeks after being invited to undergo colorectal cancer screening. For those who intended to do so, we used multivariable logistic regression analysis to determine any statistical associations between sociodemographic and medical characteristics and participation rates within 30 months.

Results: 82.7% of the respondents (239/298) intended to participate, and 43.3% (129/298) actually did so within 30 months. The participation rates among persons who had already decided to have a stool test or a colonoscopy were 50.7% (36/71) and 55.2% (58/105), respectively; the participation rate among undecided persons was 33.3% (19/57). The strongest association in the regression model was with an already made appointment (OR = 11.1, 95% confidence interval: [3.9; 31.8]). After exclusion of the existingappointment variable from the regression model, living in a smaller town (OR = 2.41 [1.08; 5.35]) and a stated preference for colonoscopy (OR = 2.52; [1.20; 5.27]) were positively associated with participation. Insurees with a parent affected by colorectal cancer participated less frequently, even after adjustment for prior colonoscopies (OR = 0.31 [0.12; 0.80]).

Conclusion: The wide gap between intended and actual participation implies that there is potential for improvement in the prevention of colorectal cancer, and that certain groups of people could benefit from targeted support in making their intention to undergo screening a reality. Because of the methodological limitations of this initial investigation, its findings need to be confirmed by further studies.