Analysing Inequalities in Colorectal Cancer Screening Using an Individual Socioeconomic Status Index

Background/Objectives: An individual socioeconomic status index (ISESI) was used to analyse inequalities in participation and colonoscopy acceptance in the Valencia Region Colorectal Cancer Screening Programme (VR-CRCSP). Methods: This is a cross-sectional study of men and women aged 50-69 who had been invited to participate in the VR-CRCSP as of February 2020 (N = 1,066,763). The variables included in the ISESI were nationality, employment status, disability, healthcare coverage, risk of vulnerability, and family size. The ISESI was categorised into quartiles (Qs), with Q4 corresponding to the lowest socioeconomic status (SES). Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using mixed logistic regression models. Results: The results showed that Q2 (OR = 1.30, CI = 1.28-1.33) and Q3 (OR = 1.07, CI = 1.05-1.09) are more likely to participate in the CRCSP than Q1 (the highest SES), and that Q4 (OR = 0.77, CI = 0.76-0.78) is less likely to participate than Q1. In addition, Q2 (OR = 2.03, CI = 1.78-2.32), Q3 (OR = 1.90, CI = 1.67-2.16), and Q4 (OR = 1.55, CI = 1.36-1.76) are more likely to accept a colonoscopy than Q1. The following socioeconomic characteristics were related to both non-participation and colonoscopy refusal: not Spanish, disabled, no family unit, at risk of social vulnerability, and private mutual health insurance. Conclusions: Inequalities were observed in VR-CRCSP participation and colonoscopy acceptance.