A Comparison of Nurse Practitioners, Physician Assistants, and Primary Care Physicians' Patterns of Practice and Quality of Care in Health Centers

Med Care. 2017 Jun;55(6):615-622. doi: 10.1097/MLR.0000000000000689.


Background: Under the Affordable Care Act, the number and capacity of community health centers (HCs) is growing. Although the majority of HC care is provided by primary care physicians (PCMDs), a growing proportion is delivered by nurse practitioners (NPs) and physician assistants (PAs); yet, little is known about how these clinicians' care compares in this setting.

Objectives: To compare the quality of care and practice patterns of NPs, PAs, and PCMDs in HCs.

Research design: Using 5 years of data (2006-2010) from the HC subsample of the National Ambulatory Medical Care Survey and multivariate regression analysis, we estimated the impact of receiving NP-delivered or PA-delivered care versus PCMD-delivered care. We used design-based and model-based inference and weighted all estimates.

Subjects: Primary analyses included 23,704 patient visits to 1139 practitioners-a sample representing approximately 30 million patient visits to HCs in the United States.

Measures: We examined 9 patient-level outcomes: 3 quality indicators, 4 service utilization measures, and 2 referral pattern measures.

Results: On 7 of the 9 outcomes studied, no statistically significant differences were detected in NP or PA care compared with PCMD care. On the remaining outcomes, visits to NPs were more likely to receive recommended smoking cessation counseling and more health education/counseling services than visits to PCMDs (P≤0.05). Visits to PAs also received more health education/counseling services than visits to PCMDs (P≤0.01; design-based model only).

Conclusions: Across the outcomes studied, results suggest that NP and PA care were largely comparable to PCMD care in HCs.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Community Health Centers*
  • Databases, Factual
  • Nurse Practitioners*
  • Patient Protection and Affordable Care Act
  • Physician Assistants*
  • Physicians, Primary Care*
  • Practice Patterns, Physicians'*
  • Primary Health Care
  • United States