Factors associated with initial participation in a population-based screening for colorectal cancer in Catalonia, Spain:A mixed-methods study

Objective: To identify barriers and facilitators associated with participation in the first round of a population-based program for colorectal cancer (CRC) in Catalonia, Spain and to identify strategies for motivating and supporting behavioral change. Material and methods: A two-part, mixed-methods design was used. In first place, a prospective study of individuals aged 50-69. years (n = 1961) was conducted in 2006-2007. Secondly, focus groups were undertaken with participants and non-participants of the CRC screening, in 2008. Results: Intention to participate was an important determinant of participation (82.9% vs 65.9%, OR = 2.56, 95%CI:1.95-3.36) in addition to knowledge about CRC and its early detection. Respondents who reported that CRC may be asymptomatic in early stages enrolled in the screening program more frequently than those who thought CRC is always symptomatic (49.4% vs 44.8%, OR:1.82; 95%CI:1.3-2.6). Barriers for participation mentioned in focus groups were competing perceived for other health problems and other demands as well as misunderstanding about personal relevance of the screening. Conclusion: Individuals' perceptions of CRC are amenable to change through education-based interventions. Increasing public knowledge related to the burden of CRC and its preventive potential may be an effective way for improving participation in a population-based screening program.