Just what the nurse practitioner ordered: Independent prescriptive authority and population mental health.

We examine whether relaxing occupational licensing to allow nurse practitioners (NPs)-registered nurses with advanced degrees-to prescribe medication without physician oversight improves population mental health. Exploiting time-series variation in independent prescriptive authority for NPs from 1990 to 2014, we find that broadening prescriptive authority leads to improvements in self-reported mental health and decreases in mental health-related mortality. These improvements are concentrated in areas that are underserved by physicians and among populations that have difficulty accessing physician-provided care. Our results demonstrate that extending independent prescriptive authority to NPs can help mitigate physician shortages and extend care to disadvantaged populations.