Author ORCID Identifier

Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

James Marton

Second Advisor

Thomas A. Mroz

Third Advisor

Keith F. Teltser

Fourth Advisor

Angela Snyder


Individuals receiving benefits from the Social Security Disability Insurance (SSDI) program have both increased health needs but potentially more limited health insurance options. Although SSDI beneficiaries qualify for Medicare after receiving 24 months worth of benefit payments, their ability to procure health insurance during the waiting period is questionable, and before the Medicare Part D expansion, their ability to acquire prescription drug insurance coverage after the waiting period was also questionable. I investigate the effects of health insurance policy on the health insurance access and outcomes for this understudied group.

In the first chapter, I investigate the effect of the Affordable Care Act on SSDI beneficiaries in the Medicare waiting period. An open question is whether SSDI beneficiaries have adequate health insurance options during the waiting period. In this study, I use difference-in-difference-in-differences estimation and data from the American Community Survey to estimate the effects of the ACA on this group. For SSDI beneficiaries in the waiting period, I estimate that the policy increased health insurance coverage by 8.3 percentage points. In Medicaid expansion states, coverage increased 12.0 percentage points, and in non-expansion states, coverage increased 3.5 percentage points. The large health insurance gains suggest that the ACA improved health insurance access during the Medicare waiting period.

In the second chapter, I investigate the effect of the Medicare Part D expansion on the prescription drug coverage, utilization, and expenditures of Medicare-eligible SSDI beneficiaries. I use difference-in-differences estimation and data from the Medical Expenditure Panel Survey (MEPS). I estimate large gains in prescription drug coverage and large decreases in annual out-of-pocket prescription drug expenditure. Additionally, the estimates suggest modest substitution away from private prescription drug coverage and little decrease in annual private insurance prescription drug expenditure. The estimates suggest large welfare gains from the policy.

In the third chapter, I investigate additional effects of the Medicare Part D expansion on Medicare-eligible SSDI beneficiaries. I look at the heterogeneous effects of the policy across this group based on demographic characteristics in the MEPS data. Additionally, I investigate how the policy affected self-reported health status. I use the same data set and a similar empirical strategy as Chapter 2. I estimate that the policy increased drug coverage more for: older individuals relative to younger individuals; individuals with some college education relative to individuals without college education; men relative to women; and married individuals relative to unmarried individuals. This led to larger decreases in out-of-pocket drug expenditure for the same subgroups. The estimates also suggest improvements in both perceived health status and perceived mental health status. I also evaluate the effects on non-prescription drug outcomes as well as prescription drugs prices, but the results are difficult to draw inference from.