A study published in the Journal of Medical Economics simulating a cohort of one million Medicare patients—US adults aged 65 years and older—with average risk of colorectal cancer, investigated the cost-effectiveness of non-invasive fecal tests (fecal immunochemical test (FIT), fecal occult blood test (FOBT), and multi target stool DNA test (mt-sDNA)). The researchers used the Colorectal Cancer and Adenoma Incidence and Mortality Microsimulation Model (CRC-AIM) with test-specific adherence data to estimate the cost-effectiveness of the various options.
Assuming 100% adherence follow-up colonoscopies and using real-world screening adherence data, the researchers found that mt-sDNA was cost-effective when compared to FOBT but not FIT. Cost-effectiveness was defined at the $100,000/quality adjusted life-year (QALY) threshold.
- $62, 814/QALY when compared to FIT
- $39,171/QALY when compared to FOBT
The assumption of100% adherence to follow-up colonoscopies is not a significant limitation to this study because this is just one scenario and also because follow-up colonoscopies are covered under Medicare. Since follow-up colonoscopies are covered under Medicare there is not a financial disincentive to get a colonoscopy and therefore most people under Medicare do get the colonoscopy. Moreover, when the authors ran the model using real-world follow up-colonoscopy and screening adherence rates, they found that mt-sDNA was even more cost-effective:
- $31,725/QALY when compared to FIT
- $28,465/QALY when compared to FOBT
Generally an incremental cost-effectiveness ratio (ICER) of less than $100,000 is considered good value, and those under $61,000/QALY is considered cost-effective. Therefore, when real-world adherence rates were considered, mt-sDNA was the more cost-effective option compared to both FIT and FOBT and resulted in greater reductions in CRC incidence and mortality.
Cost-effectiveness analyses are important for determining which screening test performs better than the others, and where to relocate resources to achieve the best health outcomes for the lowest possible cost. These types of studies on Medicare populations are important because they help policy makers make informed decisions on resource allocation.
Gargi Patel is a Colon Cancer Prevention Intern with the Colon Cancer Foundation.