Introduction: Transportation is a common barrier that limits patient access to colonoscopy, especially in safety-net healthcare systems. Screening for colorectal cancer (CRC) using a fecal immunochemical test (FIT) is cost effective but relies on colonoscopy completion after abnormal FIT results. Our preliminary research found that a rideshare non-emergency transportation (NEMT) intervention was safe, acceptable, and feasible to implement in a safety-net population that required sedation for colonoscopy completion. This study aims to determine the cost-effectiveness of providing rideshare to patients with abnormal FIT results to inform a potential Centers for Medicare and Medicaid Services (CMS) coverage decision for similar rideshare interventions.
Methods: We used the CRC-SPIN microsimulation model to project outcomes (number of CRC cases, deaths and life years) per 1000 people screened and costs associated with improved completion of follow-up colonoscopy after an abnormal FIT result. To examine age effects, we simulated five single-age cohorts (45, 55, 65, 70 or 75 at intervention), that we assumed were adherent to annual FIT screening with a baseline follow-up colonoscopy completion of 35% (no intervention). We determined the change in CRC outcomes if rideshare led to increases in follow-up colonoscopy completion, ranging from 40% to 100%. We also determined the lifetime cost of the intervention at an average ride cost of $40 and $100.
Results: Assuming a screening population of 45-year-olds, a rideshare intervention that increased colonoscopy completion by 15% (35% to 50%) would reduce CRC cases/1000 by 14.4% (35.59 vs. 41.58) and CRC deaths/1000 by 18.2% (11.95 vs. 14.60), resulting in 129,746 life years gained (LYG)/1000. At $100 per ride, the intervention would save $195,456/1000 people screened, with a direct lifetime cost of $11,539/1000 screened. If the rideshare intervention doubled colonoscopy completion in the same population (to 70%), this would reduce CRC cases/1000 by 26.3% (30.65 vs. 41.58), CRC deaths/1000 by 37.3% (9.16 vs. 14.60) and would result in 241,909 LYG/1000. Despite the decreased magnitude of benefit with age, costs also decreased with age and the intervention remained cost-saving for all age-cohorts (Figures 1 & 2).
Conclusions: Increasing colonoscopy completion in a population with abnormal FIT results via a rideshare NEMT intervention is cost-saving at either $40 or $100/ride due to the combined effect of detecting pre-cancerous lesions and CRC at an earlier stage. Rideshare NEMT is a potentially scalable intervention to improve colonoscopy completion after abnormal non-invasive screening tests, a persistent challenge in CRC screening, and should be considered in future CMS coverage decisions.

Figure 1: Colorectal cancer cases and deaths per 1000 people screened by varying adherence to colonoscopy completion after abnormal fecal immunochemical test (FIT) results
Figure 2: Net lifetime costs for colorectal cancer screening including a rideshare intervention to improve colonoscopy completion after abnormal fecal immunochemical test (FIT) results at $40/ride or $100/ride