For the vast majority of health plans offered in the private market, the provider network – including the set of hospitals, physicians, and other providers who deliver care under the terms of the insurance contract – is a key coverage feature. The size and composition of the provider network can influence an enrollee's ability to access primary and specialty care in a timely fashion. There may also be financial implications related to the provider network since expenses associated with care received from a provider outside of the network may or may not be covered, depending on the plan type. Additionally, the set of providers within a plan's network can vary in quality, which can affect patient outcomes.

Ensuring access to care is an ongoing challenge in rural America, where the healthcare workforce supply is smaller and the healthcare needs are greater. This causes challenges for insurers, consumers, and state regulatory agencies alike. One strategy that is used to help ensure access to care within insurance plans is network adequacy regulation, in which states define and enforce certain requirements for insurers' provider networks. Often these come in the form of standards around maximum allowable travel times and distances to reach primary and specialty care. However, those standards do not always account for differences by rurality in provider supply, population healthcare needs, and geographic complexities.

Health plans have increasingly adopted narrow provider networks as a cost-saving mechanism, and several studies have examined the implications of narrow networks for premiums and enrollees' ability to access care. However, limited attention has been focused on rural-specific network adequacy issues.

For this study, we reviewed the literature on network adequacy, analyzed state and federal network adequacy standards, and conducted structured interviews with representatives of state insurance departments in five states: California, Kentucky, Montana, Texas, and Wisconsin.