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Member Research & Reports

Member Research & Reports

SDSU and AHRQ Compare Effects of Medicaid and Marketplace Eligibility in Second Year of ACA’s Coverage Expansion

Affordable Care Act (ACA) provisions implemented in 2014, including Medicaid expansions in participating states and the availability of subsidized coverage in newly established health insurance Marketplaces, have been shown to have increased health insurance coverage and improved access to care among low-income adults. Most existing studies examine the full population targeted by the ACA’s Medicaid expansion — those with incomes up to 138 percent of the federal poverty level. However this group received two very different treatments in nonexpansion states depending on whether they had incomes above or below poverty, making it difficult to directly compare Medicaid and subsidized private insurance based on previous work. The recent debate over the future of the ACA makes a comparison of the two different ways the ACA extended health insurance coverage to low-income adults timely.

In the new report, published in the December issue of Health Affairs, researchers examined data from the 2008 – 2015 National Health Interview Survey (NHIS). The team assessed the effects of the ACA on adults with family incomes of 100 – 138 percent of the federal poverty level. Adults in the study either gained Medicaid eligibility in expansion states or subsidized Marketplace coverage in nonexpansion states.

The results indicate that, as of 2015, adults in expansion and nonexpansion states experienced declines in uninsurance of 22 percentage points and 18 percentage points, respectively. Fewer adults reported delaying or not seeking care due to cost, and more adults reported having a recent primary care visit in both expansion and nonexpansion states. However, adults in expansion states but not nonexpansion states reported declines in out-of-pocket healthcare spending and taking less than prescribed amounts of medicine due to cost. Adults in expansion states also reported facing more difficulty accessing a physician due to long wait times for appointments or to see a doctor compared to adults in nonexpansion states.

These findings underline the importance of studying this narrower group as the results depart substantially from those of prior studies examining the full population with incomes up to 138 percent of the federal poverty level. The results imply that both approaches to covering low-income adults improved coverage rates and access to health care. However, Medicaid compared to Marketplace eligibility also involved trade-offs in access to providers and affordability that should be considered in future policy discussions.

Study authors include Dr. Thomas Selden, director of the division of research and modeling at the Agency for Healthcare Research and Quality (AHRQ), Dr. Brandy Lipton, assistant professor, San Diego State University Graduate School of Public Health, and Dr. Sandra Decker, senior fellow, AHRQ.