Colorectal Cancer Test Completion Among Adults Aged 45–75 in an Integrated Healthcare System: A Retrospective Analysis

Abstract Background: In 2021, the U.S. Preventive Services Task Force (USPSTF) lowered the recommended age for colorectal cancer (CRC) screening from 50 to 45. This study examined CRC test completion and test modalities used among adults aged 45–49 compared to those 50 and older. Methods: We conducted a retrospective cohort study using electronic health records from an integrated academic-community health system that implemented organized screening. Adults aged 45–75 eligible for CRC screening between 2021 and 2024 were included. Outcomes were CRC test completion and test modality: colonoscopy, fecal immunochemical test (FIT), FIT-DNA, CT colonography, or flexible sigmoidoscopy. Results: Approximately 80,000 adults were eligible for screening annually. CRC test completion rose from 61.8% (2021) to 70.8% (2024), with the largest increase in the 45–49 age group (25.6% to 51.7%). Colonoscopy and FIT were the most used modalities; among 45–49-year-olds, FIT increased by 12.2% and colonoscopy by 14.2%. FIT-DNA use rose slightly, while flexible sigmoidoscopy use declined. Racial and ethnic disparities in CRC test completion decreased across groups. Conclusions: Following the 2021 USPSTF recommendation, CRC test completion improved across all age groups, especially adults 45–49. Colonoscopy and FIT use predominated. Ongoing efforts are needed to improve screening among younger adults to reach the 80% national screening goal. Impact: This study demonstrated that expanding CRC testing to 45-49-year-olds led to increased uptake of colonoscopy and FIT. It highlights how organized outreach and providing options in screening modalities can improve CRC test completion across several patient populations.