Comparison of Specialty Distribution of Nurse Practitioners and Physician Assistants in North Carolina, 1997-2013

June 15, 2015

Anna Johnson, PhD, MSPH; Erin Fraher, PhD, MPP; Perri Morgan, PhD, PA-C

Presentation at the 2015 AcademyHealth Annual Research Meeting



Nurse practitioners (NPs) and physician assistants (PAs) fill workforce needs in many specialties. Specialty distributions of NPs and PAs have changed over time, with the proportion of NPs and PAs in primary care decreasing in recent years. Although many workforce analyses assume that NPs and PAs fill similar roles, there is evidence that they fill different niches in the healthcare workforce. Few previous studies have investigated time trends in the specific specialties in which NPs and PAs practice. This study examines specialty distribution among NPs and PAs in North Carolina (NC) in 1997 and 2013 and describes specialties that have experienced an increase or decrease in the use of NPs or PAs over this period.

Research Question: How have NP and PA specialty distributions in North Carolina changed over the past 15 years?

Summary of Findings

  • Large growth in both professions led to larger numbers of NPs and PAs in most specialties
  • While the proportion of NPs in primary care changed little over time, PAs were considerably more likely to report primary care practice in 1997 than in 2013
  • Specialty distributions changed over time for both NPs and PAs
  • NP proportions increased in medical subspecialties and decreased in pediatrics and Ob/Gyn
  • PA proportions decreased in primary care, increased in medical subspecialties, and were high in urgent care in 2013

Implications for Health Workforce Research and Policy

  • The change in specialty patterns of NC NPs and PAs between 1997 and 2013 demonstrates the malleability of both professions.
  • NPs and PAs are a flexible workforce that the nation can draw upon to meet emerging healthcare needs and opportunities.
  • There are important similarities and differences between NPs and PAs that should be considered in workforce policy design
  • Future research should advance understanding of mutable factors affecting specialty choice
  • Policies to attract NPs and PAs to specialties where they are most needed should be developed, tested, and implemented


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This work is funded through cooperative agreement U81HP26495, Health Workforce Research Centers, with the National Center for Health Workforce Analysis, Bureau of Health Professions, Health Resources and Services Administration, U.S. Department of Health and Human Services. The content and conclusions are those of the authors and should not be construed as the official position or policy of, nor should any endorsements be inferred by HRSA, HHS or the U.S. Government.