Background: Age-appropriate colon cancer screening has long demonstrated effectiveness in reducing colon cancer incidence and mortality. However, despite a gradual rise in compliance with colon cancer screening, significant disparities remain, particularly among patients with limited English proficiency (LEP). Multitarget stool DNA (MT-sDNA) testing (Exact Sciences, Madison, WI) has been available over the past decade in the United States as a lower-cost and non-invasive option for screening. In 2019, Exact Sciences began to offer patient navigation services comprising outbound phone, text, and e-mail reminders, and inbound phone support (>200 languages) with all MT-sDNA orders. In this study, we aimed to evaluate the disparity in successful MT-sDNA testing between LEP and EP patients in a time frame when patient navigation services were active. Methods: We performed a retrospective cohort study of patients 45-75 years old enrolled in the primary care setting of our institution who received an order for MT-sDNA screening during a period in which patient navigation services began to be offered. A multi-state Cox model was constructed with time to MT-sDNA or other CRC screening predicted by English proficiency accounting for age and gender. Wald tests were used to test the association of CRC screening completion and English proficiency. Rates of completion of MT-sDNA screening and other CRC screening following MT-sDNA test ordering were calculated using the Kaplan-Meier method. Results: Of the 5016 patients evaluated and referred for multitarget stool DNA testing from May 1^st, 2021, and May 1^st, 2022, 154 patients were of LEP, and 4862 were English proficient (EP). At 180 days following a MT-sDNA test order the rate of completion for the LEP patients was 50.2% (95% CI: 42.8-58.7%) versus 70.3% (95% 69.1-71.6%) for EP individuals (p=0.001). A small portion of individuals also completed another type of CRC screen, 3.3% for LEP and 2.5% for EP (p=0.99). Conclusions: This study is consistent with the existing research demonstrating LEP as a significant demographic group linked with decreased participation in cancer screening. Our findings indicated that despite the availability of patient navigation services, individuals with LEP were still less likely to complete an MT-sDNA test successfully when compared to those with EP.

*Adjusted for age and gender.