Policy Diffusion across Disparate Disciplines: Private- and Public-Sector Dynamics Affecting State-Level Adoption of the ACA.

The ACA entails a number of provisions that are profoundly changing the way the states ensure access to medical care, including the expansion of Medicaid and the maintenance of health insurance exchanges. Here, we argue that while federal policy is the originating force of whether these provisions are adopted, individual state decisions are made within a larger ecosystem. This ecosystem has two main components: (1) complementary and competing state and federal policies; and (2) medical provision by a variety of suppliers. Specifically, the merits, costs, and uncertainties associated with adopting these provisions cannot be considered by the states in a vacuum-they may interact with a large set of simultaneously launched or existing local, state, and federal policies aimed at ensuring access to medical care. They may also interact with specific state and federal reimbursement policies and other requirements facing local hospitals and medical providers. We illustrate by example how these interactions may have important implications for the diffusion of ACA provisions. One implication of this perspective is that future empirical work on the rate, determinants, and impacts of ACA coverage expansions on individual and aggregate well-being must incorporate systematic study of this complex public-private sector ecosystem.