The role of disgust as an emotional barrier to colorectal cancer screening participation: a systematic review and meta-analysis

Objective: Worldwide colorectal cancer (CRC) screening rates are suboptimal. This systematic review and meta-analysis examine the role of disgust in CRC screening avoidance. Design: A systematic literature search was conducted. In all, 46 studies were included in the review. Among these, 16 studies were compared with a meta-analytical approach in order to 1) estimate the effect size of state disgust on screening intention and attendance; 2) examine whether methodological characteristics moderate the effect of state disgust on screening behaviour; 3) estimate the effect sizes of trait disgust and type of exam kit on state disgust. Results: In the reviewed studies, state disgust was often associated with CRC screening and especially with CRC screening avoidance. The meta-analysis confirmed low-to-moderate negative effects of state disgust on screening intention and attendance. Population sampling strategy was the only significant moderator of the effect of state disgust on screening attendance, i.e. studies that used convenience (versus random/representative) samples found a significantly lower effect size. Trait disgust and type of exam kit exerted a large and a moderate-to-large positive effect, respectively, on state disgust. Conclusions: Disgust can boost CRC screening avoidance. Further studies and interventions must be designed to help patients in overcoming this emotional barrier.