Medicaid hurts the poor. The now-infamous University of Virginia study "Primary Payer Status Affects Mortality for Major Surgical Operations.”:

The study evaluated 893,658 major surgical operations occurring between 2003 and 2007, stratified by primary payer status, on three outcomes endpoints: in-hospital mortality, length of stay, and total costs incurred.

Despite the fact that the authors controlled for age, gender, income, geographic region, operation, and 30 comorbid conditions, Medicaid fared poorly compared to those with private insurance, Medicare, and even the uninsured. Relative to those with private insurance, Medicare, uninsured, and Medicaid patients were 45%, 74%, and 97% more likely to die in the hospital post-operatively.