The Impacts of the ACA Medicaid Expansions on Cancer Screening Use by Primary Care Provider Supply
Background: Recent studies of the impacts of the Affordable Care Act (ACA) Medicaid expansions on cancer screening use have mostly found insignificant effects. We posit that these findings mask meaningful heterogeneity in impacts depending on availability of primary care providers. Objective: This study examined the impacts of the ACA Medicaid expansions on cancer screening use separately by state-level supply of primary care providers. Research Design: We used data from the 2012 and 2016 Behavioral Risk Factor Surveillance System surveys to measure use of mammograms, Pap smear tests, blood stool tests, and sigmoidoscopy/colonoscopy for age groups recommended receiving these tests. The main analytical sample included 24,878-31,890 individuals with household income below 138% Federal Poverty Line. We used a difference-in-differences design comparing pre-post expansion changes in cancer screening use between expanding and nonexpanding states separately for 2 state groups defined by the median proportion of the state population residing in primary health professional shortage areas: low primary care provider supply (above median) and high supply (below median). Results: Medicaid expansions were associated with significant increases in mammograms (11.4 percentage-points), Pap smear tests (6.9 percentage-points), and sigmoidoscopy/colonoscopy use (8.3 percentage-points) in states with high supply of primary care providers. In contrast, effects were small and insignificant in low supply states. Conclusions: ACA Medicaid expansions were associated with increased cancer screening use only in states with high supply of primary care providers. Improving access for Medicaid beneficiaries in provider shortage areas may require coupling coverage expansions with supply-side interventions to increase provider availability.
Lyu, Wei and Wehby, George L., "The Impacts of the ACA Medicaid Expansions on Cancer Screening Use by Primary Care Provider Supply" (2019). Health Systems Management and Policy Division Faculty Publications. 89.