Association of State-Level Restrictions in Nurse Practitioner Scope of Practice With the Quality of Primary Care Provided to Medicare Beneficiaries.

State scope of practice (SoP) laws impose significant restrictions on the services that a nurse practitioner (NP) may provide in some states, yet evidence about SoP limitations on the quality of primary care is very limited. This study uses six different classifications of state regulations and bivariate and multivariate analyses to compare beneficiaries attributed to primary care nurse practitioners and primary care physicians in 2013 testing two hypotheses: (1) chronic disease management, cancer screening, preventable hospitalizations, and adverse outcomes of care provided by primary care nurse practitioners are better in reduced and restricted practice states compared to states without restrictions and (2) by decreasing access to care, SoP restrictions negatively affect the quality of primary care. Results show a lack of consistent association between quality of primary care provided by NPs and state SoP restrictions. State regulations restricting NP SoP do not improve the quality of care.