As hospitals' interest in nurse practitioners (NPs) and physician assistants (PAs) grows, their leadership is eager to know how their medical staffing privileging policies for these professionals compare to peer hospitals. This study assesses the extent of variation of these policies in four clinical areas and examines whether the differences are associated with state scope of practice laws for NPs and PAs. We also examine the relationship of NP and PA privileging policies to each other. Our analysis finds no evidence that hospital privileging is associated with state scope of practice, and indeed within-state variation is more significant than cross-state variation. We also find a strong correlation between NP and PA privileging in all four clinical areas. These results suggest the need for additional research to understand the institutional-level variables and human dynamics at the level of medical staffing committees that may explain the dramatic variation in privileging policies and, ultimately, the effects of different privileging levels on costs and quality.
Keywords: hospital privileging; nurse practitioner; physician assistant; scope of practice.