Nurse Practitioner Independent Practice Authority and Mental Health Service Delivery in US Community Health Centers

Objective: Little is known about how nurse practitioner independent practice authority (NP-IPA) influences patient care. This study examined the effect of NP-IPA on patterns of mental health-related visits provided by NPs in U.S. community health centers (CHCs). Methods: State NP regulatory information was linked to National Ambulatory Medical Care Survey data on NP-and physician-provided visits (N=61,457) in CHCs from 2006 through 2011. The proportion of NP-provided versus physician-provided mental health-related visits in states with NP-IPA was compared with the proportion in states without NP-IPA. The adjusted odds of mental health-related visits in CHCs provided by NPs in states with and without NP-IPA were compared by using multiple logistic regression models while accounting for the complex survey design. Results: Between 2006 and 2011, the odds of NP-versus physician-provided mental health-related visits in CHCs were more than two times greater in states with NP-IPA than in states with no NP-IPA (adjusted odds ratio [ OR]=2.43, 95% confidence interval [CI]=1.12-4.60). In contrast, no significant difference between states with and without NP-IPA was noted in non-mental health-related CHC visits provided by NPs. Among all mental health-related visits, the odds of visits in which psychotropic medications were prescribed by an NP were more than three times higher in states with NP-IPA than in those without NP-IPA (adjusted OR=3.14, CI=1.50-6.54). Conclusions: Compared with physicians, NPs provided proportionally more CHC mental health-related visits in states with NP-IPA than in states without NP-IPA.