Adherence to Obstetrician-/Gynecologist-Ordered Multi-target Stool DNA Test Screening and Follow-Up Colonoscopy: A National Multi-payer Study of US Women

INTRODUCTION: Colorectal cancer (CRC) screening remains below national targets among US women. Primary care providers (PCPs) play an important role in promoting CRC screening adherence. Many US women see an obstetrician/gynecologist (OB/GYN) as their PCP. We evaluated adherence among US women to multi-target stool DNA (mt-sDNA) testing and follow-up colonoscopy ordered by OB/GYNs. METHODS: We linked Exact Sciences Laboratories (ESL) orders with a national multi-payer claims database (2016-2022). Eligible participants were average-risk women aged 45-75 years with continuous health plan enrollment (- 180 to 0 days baseline; 0-365 days to assess mt-sDNA adherence; and, after a positive mt-sDNA result, 0-365 days to assess colonoscopy). Primary outcomes were mt-sDNA completion within 365 days of kit shipment and colonoscopy completion within 365 days of a positive mt-sDNA test. Logistic regression evaluated factors associated with mt-sDNA adherence. RESULTS: Of 160,068 women with OB/GYN-ordered mt-sDNA, 71.4% (n = 114,360/160,068) completed testing within 365 days. Test positivity was 8.6% (n = 9773/114,360). Among those with positive results, 71.3% (n = 6971/9773) completed colonoscopy within 365 days. Test adherence increased with age (45-49 years, 67.1%; 50-64 years, 71.8%; 65-75 years, 76.7%), was higher in non-metropolitan areas, and rose with higher ZIP code median household income. Test adherence was higher among individuals with traditional Medicare (85.2%) and Medicare Advantage (77.3%) than commercial insurance (71.3%) and Medicaid (61.7%). CONCLUSION: In routine practice, more than 70% of women completed OB/GYN-ordered mt-sDNA testing and, after a positive result, more than 70% completed colonoscopy within 1 year. OB/GYN clinicians may play a key role in improving CRC screening adherence, with opportunities to address gaps by payer, income, and race/ethnicity.