Disparities in Rates of Multitarget Stool DNA Test Completion for Colorectal Cancer Screening

Abstract

Goals: The aim was to assess patient adherence to multitarget stool DNA testing as well as factors associated with adherence. Background: In the United States, disparities in colorectal cancer screening exist along racial and socioeconomic lines. While some studies suggest that stool-based screening tests may help reduce the screening gap, the data for multitarget stool DNA testing is unclear. Study: We conducted a single-center retrospective cohort study on multitarget stool DNA testing ordered between April 2020 and July 2021. We calculated the proportion of patients who completed testing and used multivariate logistic regression to identify covariates associated with test adherence. Results: Among 797 patients ordered for multitarget stool DNA testing, 481 patients (60.4%) completed testing. Adherence rates by patient subgroups ranged from 35.8% to 78.1%. Higher test adherence was found in Asian patients (odds ratio 2.65, 95% CI 1.36-5.18) and those who previously completed colorectal cancer screening (OR 1.45, 95% CI 1.01-2.09), while Black patients (OR 0.58, 95% CI 0.39-0.87), patients with resident primary care physicians (OR 0.34, 95% CI 0.21-0.56), and patients contacted through an outreach program (OR 0.47, 95% CI 0.25-0.87) had lower adherence. Conclusions: A significant proportion of patients ordered for multitarget stool DNA testing did not complete testing. Differences in adherence rates among patient subgroups may be reflective of underlying disparities in health care access.