Scope of Practice and Patient Panel Size of Family Physicians Who Work With Nurse Practitioners or Physician Assistants

BACKGROUND AND OBJECTIVES: Little is known about how the presence of nurse practitioners (NPs) and physician assistants (PAs) in a practice impacts family physicians’ (FPs’) scope of practice. This study sought to examine variations in FPs’ practice associated with NPs and PAs. METHODS: We obtained data from American Board of Family Medicine practice demographic questionnaires completed by FPs who registered for the Family Medicine Certification Examination during 2013-2016. Scope of practice score was calculated for each FP, ranging from 0-30 with higher numbers equating to broader scope of practice. FPs self-reported patient panel size. Primary care teams were classified into NP only, PA only, both NP and PA, or no NP or PA. We estimated variation in scope and panel size with different team configurations in regression models. RESULTS: Of 27,836 FPs, nearly 70% had NPs or PAs in their practice but less than half (42.5%) estimated a panel size. Accounting for physician and practice characteristics, the presence of NPs and/or PAs was associated with significant increases in panel sizes (by 410 with PA only, 259 with NP only and 245 with both; all P<0.05) and in scope score (by 0.53 with PA only, 0.10 with NP only and 0.51 with both; all P<0.05). CONCLUSIONS: We found evidence that team-based care involving NPs and PAs was associated with higher practice capacity of FPs. Working with PAs seemed to allow FPs to see a greater number of patients and provide more services than working with NPs. Delineation of primary care team roles, responsibilities and boundaries may explain these findings.