Volume 54 | Number S1 | February 2019

Abstract List

Charles Courtemanche Ph.D., James Marton Ph.D., Benjamin Ukert PhD, Aaron Yelowitz Ph.D., Daniela Zapata PhD, Ishtiaque Fazlul MA


To estimate the impact of the major components of the (Medicaid expansion, subsidized Marketplace plans, and insurance market reforms) on disparities in insurance coverage after three years.

Data Source

The 2011‐2016 waves of the American Community Survey (), with the sample restricted to nonelderly adults.


We estimate a difference‐in‐difference‐in‐differences model to separately identify the effects of the nationwide and Medicaid expansion portions of the using the methodology developed in the recent literature. The differences come from time, state Medicaid expansion status, and local area pre‐ uninsured rates. In order to focus on access disparities, we stratify our sample separately by income, race/ethnicity, marital status, age, gender, and geography.

Principal Findings

After three years, the fully implemented eliminated 43% of the coverage gap across income groups, with the Medicaid expansion accounting for this entire reduction. The also reduced coverage disparities across racial groups by 23%, across marital status by 46%, and across age‐groups by 36%, with these changes being partly attributable to both the Medicaid expansion and nationwide components of the law.


The fully implemented has been successful in reducing coverage disparities across multiple groups.