Lisa Dubay, PhD, is Senior Fellow at the Urban Institute. Dr. Dubay recently returned to the Urban Institute after being an Associate Professor at the Johns Hopkins Bloomberg School of Public Health and a Special Advisor in the Office of the Assistant Secretary for Planning and Evaluation. Dr. Dubay is a nationally recognized expert on the Medicaid and CHIP programs. She is a health services researcher who has focused on evaluating the effects of public policies on access to care, health care utilization, health outcomes and health insurance coverage using quasi-experimental designs. Dr. Dubay's evaluation work has included assessing the impacts of expansions in public health insurance programs for children, pregnant women and adults for federal agencies and major foundations. She has also assessed the impact of the movement to Medicaid managed care on access to care and health outcomes. Her early work focused evaluating the impact of Medicaid nursing home reimbursement strategies on quality of care and health outcomes of residents and of Medicare's hospital prospective payment system on hospital, nursing home and home health use under Medicaid and Medicare. Dr. Dubay developed the Health Policy Center's Medicaid eligibility simulation model which she has used to produce estimates of eligible but uninsured children and participation rates in Medicaid and CHIP.