Screening
Addressing the immigrant screening gap: A systematic review on interventions to increase colorectal cancer screening among immigrants in the United States Ethan Cohen* Taylor McCready McCready New York University Grossman School of Medicine
Introduction
Interventions to increase colorectal cancer (CRC) screening among US immigrants are increasing, but a rigorous systematic review has not been conducted. Definitions of immigrant and screening outcomes vary widely, limiting synthesis and transportability.
Methods
We searched English-language peer-reviewed and grey literature (January 1, 2000 and April 30, 2025) in PubMed, Cochrane Library, CINAHL (EBSCO), ClinicalTrials.gov, Embase, Scopus, and Web of Science. Two reviewers independently screened and extracted data in Covidence. Risk of bias was assessed using the Risk of Bias 2 (ROB2) tool for randomized controlled trials, and the Risk of Bias in Non-Randomized Studies of Interventions (ROBINS-I) tool for other study designs. Quantitative synthesis was restricted to studies explicitly defining immigrants in the analytic population (PROSPERO: CRD42023488183).
Results
The primary outcome was CRC screening completion. Of 1,824 unique records, 45 studies were included (39 randomized trials, 6 non-randomized), totaling > 21,000 participants. Individualized education (n=12), navigation-based interventions (n=17; including patient navigation alone and navigation plus culturally targeted materials), and non-individualized educational campaigns (n=7) were the most evaluated strategies, alongside mailed and telephone outreach with fecal tests (n=4). Among trials reporting screening outcomes in intervention and control arms (n=19), interventions increased screening by an average of 20% versus control, with culturally tailored navigation-based approaches generally yielding the largest gains. Heterogeneity in immigrant definitions, settings, and outcomes limited cross-population comparisons and precluded a meta-analysis.
Conclusion
Tailored navigation is the most consistently effective approach, but inconsistent measurement of immigrant status and screening outcomes limit transportable inference; standardization is a priority for future trials and evidence synthesis.