Socioeconomic Inequalities in Participation in Colorectal Cancer Screening in Ontario, Canada: A decomposition analysis.

Background: The relationship between socioeconomic status and colorectal cancer (CRC) screening in Canada remains poorly understood. This study aims to measure and explain the extent of socioeconomic inequalities in CRC screening participation in Ontario, Canada.
Methods: This study assesses socioeconomic inequalities in CRC screening uptake in Ontario among adults aged 50 to 74 years (n=12,039) utilizing cross-sectional data from the 2017-2018 Canadian Community Health Survey (CCHS). The Wagstaff Index (WI) and the Erreygers Index (EI) were used to quantify and decompose income-related inequality in CRC screening participation.
Results: The results revealed an overall CRC screening rate of 71.7%, with higher rates among females (78.4%) compared to males (69.4%). The positive values of the WI (0.193; 95% confidence interval [CI]: 0.170 to 0.215) and the EI (0.156; 95% CI: 0.138 to 0.174) indicated a pro-rich inequality in CRC screening participation in Ontario (i.e., screening is more concentrated among wealthier individuals). The decomposition analysis identified income (71.61%), education (8.61%), and language barriers with healthcare providers (5.76%) as the primary factors contributing to the observed income-related inequality in CRC screening participation.
Conclusion: Income is the primary driver of socioeconomic inequality, requiring targeted strategies to boost screening rates among low-income residents. Addressing education and language barriers through awareness initiatives and language support can reduce socioeconomic inequalities in cancer screening uptake in Ontario.
Impact: Our study reveals significant socioeconomic inequality in colorectal cancer screening in Ontario, driven by income, education, and language barriers, underscoring the need for targeted interventions to promote equitable access.