Sehgal M, Ladabaum U, Mithal A, et al. - In view of an increasing incidence of colorectal cancer (CRC) at ages < 50 years, proposals have been made to lower the CRC screening initiation age to 45 years. Researchers sought to obtain data on the effectiveness of CRC screening at ages 45-49 years via a retrospective population-based cohort study using Florida’s linked Healthcare Cost and Utilization Project databases with mandated reporting from 2005-2017. From 195,600 participants with and 2.6 million without a colonoscopy at ages 45-49 years, CRC developed in 276 and 4,844 persons, indicating CRC incidence rates of 20.8 and 30.6 per 100,000 person-years, respectively. From 660,248 participants with and 2.4 million without colonoscopy at ages 50-54 years, CRC development was reported in 798 and 6,757, resulting in CRC incidence rates of 19.0 and 51.9 per 100,000 person-years, respectively. Findings revealed substantial reductions in ensuing CRC incidence in correlation with undergoing colonoscopy at ages 45-49 years or 50-54 years.