Why Are so Many Americans Uninsured? a Conceptual Framework, Summary of the Evidence, and Delineation of the Gaps in Our Knowledge

Numerous data sets are available which allow us to count and describe the socio-economic characteristics of the uninsured in the US. While these data differ on precise estimates, by all accounts the number of uninsured is large (around 40 million in the best of economic times) and prone to grow, both in absolute terms along with the population and as a percentage of the population when the economy weakens. There is some dispute about whether the widespread lack of insurance is a market failure that justifies policy intervention, and we address this issue in our theoretical discussion below. There is less controversy about the substantial body of research which demonstrates that the uninsured have reduced access to care. Many researchers have also concluded that the uninsured often have inferior medical outcomes when an injury or illness occurs. Regardless of final analytic judgments about causation between health