OBJECTIVES: Guidelines recommend colorectal cancer (CRC) screening for adults 50-75 years. While stool-based tests (SBTs) including fecal immunochemical tests (FIT), high-sensitivity guaiac fecal occult blood tests (gFOBT), and stool DNA (sDNA) tests can be used, a positive SBT requires follow-up with colonoscopy to achieve the benefits of CRC screening. This study aimed to assess follow-up colonoscopy rates within 6 months after a positive SBT.

METHODS: This was a retrospective analysis of de-identified SBT results data linked with de-identified administrative claims for commercially insured and Medicare Advantage enrollees in the OptumLabs Data Warehouse. Patients 50-75 years with a valid positive SBT result between 01/01/2017-10/31/2022, continuous enrollment for 360 days before and 180 days after the SBT date, and without CRC, high-risk conditions, or screening procedures in the 360-day baseline period were included. The presence of a colonoscopy procedure claim was evaluated in the 180-day follow-up period.

RESULTS: Overall, 67,424 positive SBT results were identified. Patient age averaged 66.6 (SD 6.7) years; 34,277 (50.8%) were female; 13,254 (19.7%) had commercial and 54,170 (80.3%) Medicare Advantage insurance.

Follow-up colonoscopy rates among positive tests were 46.9% overall (31,613 of 67,424 tests). Follow-up colonoscopies for positive tests increased from 38.5% (3,874 of 10,069 tests) in 2017, 40.7% (4,023 of 9,881 tests) in 2018, 41.4% (4,057 of 9,806 tests) in 2019, and 39.0% (3,485 of 8,926 tests) in 2020 to 55.7% (9,861 of 17,715 tests) in 2021 and 57.3% (6,313 of 11,027 tests) in 2022.

CONCLUSIONS: Follow-up colonoscopy rates among patients with positive SBT improved from 2017 to 2022 but remain suboptimal. In 2021-2022, 43% of patients with a positive SBT did not complete the recommended follow-up colonoscopy and did not receive the benefits of CRC screening. Future studies are warranted to investigate differences in follow-up colonoscopy rates by SBT type and barriers to colonoscopy.