Background
To reduce colorectal cancer (CRC) mortality, positive fecal blood tests must be followed by colonoscopy.
Methods
We identified 62,384 individuals aged 50–89 years with a positive fecal blood test between 1/1/2011 and 12/31/2012 in four healthcare systems within the Population-Based Research Optimizing Screening through Personalized Regimens (PROSPR) consortium. We estimated the probability of follow-up colonoscopy and 95% confidence intervals (CIs) using the Kaplan-Meier method. Overall differences in cumulative incidence of follow-up across health care systems were assessed with the log-rank test. Hazard ratios and 95% CIs were estimated from multivariate Cox proportional hazards models.
Results
Most patients who received a colonoscopy did so within six months of their positive fecal blood test, although follow-up rates varied across healthcare systems (p <0.001). Median days to colonoscopy ranged from 41 (95% CI, 40–41) to 174 (95% CI, 123–343); percent followed-up by 12-months ranged from 58.1% (95% CI, 51.6%–63.7%) to 83.8% (95% CI, 83.4%–84.3%) and differences across healthcare systems were also observed at 1, 2, 3, and 6 months. Increasing age and comorbidity score were associated with lower follow-up rates.
Conclusion
Individual characteristics and healthcare system were associated with colonoscopy after positive fecal blood tests. Patterns were consistent across healthcare systems, but proportions of patients receiving follow-up varied. These findings suggest there is room to improve follow-up of positive CRC screening tests.
Impact
Understanding the timing of colonoscopy after positive fecal blood tests and characteristics associated with lack of follow-up may inform future efforts to improve follow-up.