Diagnostic colonoscopy following a positive fecal occult blood test in community health center patients

David T. Liss, Tiffany Brown, Ji Young Lee, Marjorie Altergott, David R. Buchanan, Anne Newland, Jessica N. Park, Sarah S. Rittner, David W. Baker

Fecal occult blood testing (FOBT) is a pragmatic screening option for many community health centers (CHCs), but FOBT screening programs will not reduce mortality if patients with positive results do not undergo diagnostic colonoscopy (DC). This study was conducted to investigate DC completion among CHC patients. This retrospective cohort study used data from three CHCs in the Midwest and Southwest. The primary study outcome was DC completion within 6 months of positive FOBT among adults age 50-75. Patient data was collected using automated electronic queries. Manual chart reviews were conducted if queries produced no evidence of DC. Poisson regression models described adjusted relative risks (RRs) of DC completion. The study included 308 patients; 63.3 % were female, 48.7 % were Spanish speakers and 35.7 % were uninsured. Based on combined query and chart review findings, 51.5 % completed DC. Spanish speakers were more likely than English speakers to complete DC [RR 1.19; 95 % confidence interval (CI) 1.04-1.36; P = 0.009], and DC completion was lower among patients with 0 visits than those with 1-2 visits (RR 2.81; 95% CI 1.83-4.33; P < 0.001) or ≥3 visits (RR 3.06; 95% CI 1.57-5.95; P = 0.001). DC completion was low overall, which raises concerns about whether FOBT can reduce CRC mortality in practice. Further research is needed to understand whether CHC navigator programs can achieve very high DC rates. If organizations use FOBT as their primary CRC screening approach and a substantial number of patients receive positive results, both screening rates and DC rates should be measured.