Advanced Practice Registered Nurse Full Practice Authority, Provider Supply, and Health Outcomes: A Border Analysis.

Due to a growing physician shortage, patients have difficulty accessing primary care. In an effort to expand access and support patient health, many states are reducing barriers for advanced practice registered nurses to provide primary care without physician collaboration. Maryland provides an interesting case study. We leverage Maryland's policy change to explore the effects of full practice authority (FPA), focusing on the number of professionals and health outcomes for patients. Employing a border county comparison between Maryland and Pennsylvania, we estimate the effect of FPA. Our analysis of health outcomes focuses on three county-level health outcomes: poor or fair health, poor mental health days, and preventable hospital stays. We find that FPA is associated with increases in the number of certified nurse midwives by 0.6 per 100,000 residents and nurse practitioners by 22.4 per 100,000 residents. We also find evidence of an association of FPA with reductions in the share of residents who report being in poor or fair health by 2.8 percentage points and poor mental health days per month by 0.354 days per person. Combined, our results provide suggestive evidence that moving to FPA improves access to care and leads to improved health outcomes for Maryland residents. Removing regulatory barriers that prevent certified nurse midwives and nurse practitioners from working to the full extent of their training may increase access to primary care and improve patient outcomes.