Medicaid Expansions and The Crowding Out of Private Health Insurance

In this paper, we re-examine the question of crowd out among children. Our primary contribution is the use of longitudinal data. These data allow us to identify several groups of children depending on whether their eligibility for Medicaid was affected by the eligibility expansions, and to investigate whether changes in insurance coverage of children affected by the expansions differed from changes in insurance coverage of children unaffected by the expansions. For example, we directly measure whether children who became eligible for Medicaid due to the expansions decreased their enrollment in private insurance plans faster than children whose eligibility for Medicaid was unaffected by the expansions. Our results suggest that there was relatively little crowd out among children. We estimate that 14.5 percent of the recent increase in Medicaid enrollment came from private insurance.