Geographic and population-level disparities in colorectal cancer testing: A multilevel analysis of Medicaid and commercial claims data

Morbidity and mortality from colorectal cancer (CRC) can be attenuated through guideline concordant screening and intervention. This study used Medicaid and commercial claims data to examine individual and geographic factors associated with CRC testing rates in one state (Oregon). A total of 64,711 beneficiaries (4516 Medicaid; 60,195 Commercial) became newly age-eligible for CRC screening and met inclusion criteria (e.g., continuously enrolled, no prior history) during the study period (January 2010-December 2013). We estimated multilevel models to examine predictors for CRC testing, including individual (e.g., gender, insurance, rurality, access to care, distance to endoscopy facility) and geographic factors at the county level (e.g., poverty, uninsurance). Despite insurance coverage, only two out of five (42%) beneficiaries had evidence of CRC testing during the four year study window. CRC testing varied from 22.4% to 46.8% across Oregon's 36 counties; counties with higher levels of socioeconomic deprivation had lower levels of testing. After controlling for age, beneficiaries had greater odds of receiving CRC testing if they were female (OR 1.04, 95% CI 1.01-1.08), commercially insured, or urban residents (OR 1.14, 95% CI 1.07-1.21). Accessing primary care (OR 2.47, 95% CI 2.37-2.57), but not distance to endoscopy (OR 0.98, 95% CI 0.92-1.03) was associated with testing. CRC testing in newly age-eligible Medicaid and commercial members remains markedly low. Disparities exist by gender, geographic residence, insurance coverage, and access to primary care. Work remains to increase CRC testing to acceptable levels, and to select and implement interventions targeting the counties and populations in greatest need.