Factors associated with organized and non-organized colorectal cancer screening

Abstract

Abstract Background Data on non-organized colorectal cancer screening using fecal occult blood tests (FOBTs) is currently lacking. We identified factors associated with organized and non-organized FOBT screening. Methods Data of 308 municipalities in Flanders (6.6 million residents, 57% of Belgium) during 2015-2017 were analyzed. Logistic regression with generalized estimating equations was used to assess associations between municipal characteristics and organized and non-organized screening coverages. Results Median organized screening coverage increased (36.4% to 40.1%) while non-organized screening coverage decreased (4.8% to 3.3%) in 2015-2017. Organized screening coverage was negatively associated with average income (OR = 0.97, 95%CI: 0.96-0.98) and percentage of people with a non-Belgian/Dutch nationality (OR = 0.962, 95%CI: 0.957-0.967). More older people (70-74) in the target screening population were related to lower coverages by both organized (OR = 0.98, 95%CI: 0.97-0.99) and non-organized screening (OR = 0.98, 95%CI: 0.96-0.999). Education level was positively associated with organized screening coverage (OR = 1.010, 95%CI: 1.008-1.011). While GP visit was positively associated with both organized and non-organized screening coverages, average number of patients per GP and having a global medical dossier handled by preferred GP showed more pronounced associations with non-organized screening (OR = 1.021, 95%CI: 1.016-1.026 and OR = 1.025, 95%CI: 1.018-1.031, respectively) compared to organized screening coverage. Conclusions Higher average income, lower average education level, more older people and people with foreign nationality were associated with lower organized screening coverage. GP involvement showed a positive association with non-organized screening. It seems that some GPs and screening-invited individuals are still not fully aware of the benefits of organized screening. Available instruments in screening programs should be optimized to fill this gap in knowledge. Key messages We identified factors associated with both organized and non-organized colorectal cancer screening using fecal occult blood tests (FOBTs). Based on this knowledge, strategies can be developed to promote screening among non-participants and encourage non-organized participants to switch to organized screening.