Impact on immigrant screening adherence with introduction of a population-based colon screening program in Ontario, Canada

Abstract

Introduction: The literature suggests that differential colorectal cancer (CRC) screening adherence exists between Canada's immigrant and nonimmigrant populations. This study explores the impact of Ontario's population screening program, ColonCancerCheck, on CRC screening uptake in immigrant and nonimmigrant population groups.

Methods: Data from 2005, 2007-2008, and 2011-2012 was obtained from the Canadian Community Health Survey, to represent the intervention periods (the time periods before, during, and after implementation of the ColonCancerCheck intervention). Multivariable logistic regression was used to examine the effect of immigration status on the risk of nonadherence to guideline-recommended CRC screening, and an interaction analysis was performed to determine whether the screening differential between immigrant and nonimmigrant populations changed upon introduction of the ColonCancerCheck program.

Results: Recent and long-term immigrants were both at increased risk of CRC screening nonadherence compared to the Canadian-born population (OR 3.73 (CI 2.25-6.18) and OR 1.24 (CI 1.13-1.36), respectively). While not statistically significant, there was an attenuation of the risk of nonadherence to screening for recent immigrants compared with Canadian-born individuals after the implementation of the ColonCancerCheck program.

Conclusions: This study provides evidence of a screening differential between immigrants and nonimmigrants, and suggests that the implementation of the ColonCancerCheck screening program in Ontario may have increased colon screening uptake amongst recent immigrants. Further studies are needed to address the factors leading to inequities in immigrant CRC screening adherence.

Keywords: cancer screening; colon cancer; colorectal cancer; equity; immigrant health; program evaluation.