Mailed Outreach for Colorectal Cancer Screening in Community Health Centers: The CARES Pragmatic Cluster Randomized...

Colorectal cancer (CRC) is the second most common cause of cancer mortality in the US and disproportionately impacts individuals in underresourced settings.

To compare 2 mailed population outreach approaches to increase CRC screening uptake among screening-eligible adults in community health centers (CHCs).

This pragmatic cluster randomized clinical trial was conducted in 8 CHCs and an additional site in a nonrandomized parallel protocol. The CHCs were located in the greater Boston area in Massachusetts and Los Angeles County in California (randomized sites), and Rapid City, South Dakota (parallel site). Patients were enrolled in the trial between June 7, 2023, and October 24, 2023. English- or Spanish-speaking primary care patients aged 45 to 75 years, who were due for CRC screening, were eligible to participate.

Patients received either mailed fecal immunochemical test (FIT) with automated text message outreach from study personnel or mailed FIT-DNA with the manufacturer's outreach protocol. Participants in Boston and Los Angeles (randomized sites) with an abnormal FIT or FIT-DNA result were offered standardized navigation to colonoscopy.

The primary outcome was CRC screening participation using any modality (FIT, FIT-DNA, or colonoscopy) within 90 days. Secondary outcomes were screening within 180 days and time to screening participation. The completion of follow-up colonoscopy within 180 days of an abnormal stool test result was also studied.

Among 5127 participants in the RCT regions, 2435 (47.5%) were in the FIT group, and 2692 (52.5%) were in the FIT-DNA group. The mean (SD) age was 54.5 (8.1) years; 3018 (58.9%) were female, and 2109 (41.1%) were male. There were 3818 Hispanic individuals (74.5%), 369 non-Hispanic Black individuals (7.2%), 763 non-Hispanic White individuals (14.9%), and 58 individuals of another race (1.1%). A total of 3363 individuals (65.6%) preferred the Spanish language; 2540 (49.5%) were Medicaid insured, and 614 were (12.0%) uninsured. Screening participation was significantly higher in the FIT-DNA group vs the FIT group at 90 days (751 of 2692 [27.9%] vs 550 of 2435 [22.6%], respectively; P = .02) and 180 days (854 of 2692 [31.7%] vs 649 of 2435 [26.7%], respectively). In Boston, screening participation at 90 days was higher (628 of 2208 [28.4%]) than in Los Angeles (673 of 2919 [23.1%]). Findings were similar at 180 days. Among the 100 individuals with an abnormal stool test result, 36 (36.0%) completed a colonoscopy within 180 days.

In this cluster randomized clinical trial, CRC screening uptake was higher in the FIT-DNA group than in the FIT group and was higher in Boston compared to Los Angeles CHCs. The follow-up colonoscopy rate within 6 months was suboptimal, even with the availability of navigation.

ClinicalTrials.gov Identifier: NCT05714644.