Medicaid expansions and the crowding out of private health insurance among children.

This paper re-examines the magnitude of crowd out among children. We use longitudinal data that allow us to identify and differentiate groups of children based on whether their eligibility for Medicaid was affected by the program's eligibility expansions. We 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 there was a greater decrease in private insurance coverage among children who became eligible for Medicaid than among children whose eligibility was unaffected. Our results suggest that there was relatively little crowd out among children. We estimate that 18.9% of the recent increase in Medicaid enrollment came from private insurance.