Working Paper: NBER ID: w19172
Authors: Kevin M. Stange
Abstract: Nurse practitioners (NPs) and physician assistants (PAs) now outnumber family practice doctors in the United States and are the principal providers of primary care to many communities. Recent growth of these professions has occurred amidst considerable cross-state variation in their regulation, with some states permitting autonomous practice and others mandating extensive physician oversight. I find that expanded NP and PA supply has had minimal impact on the office-based healthcare market overall, but utilization has been modestly more responsive to supply increases in states permitting greater autonomy. Results suggest the importance of laws impacting the division of labor, not just its quantity.
Keywords: health care market; nurse practitioners; physician assistants; provider supply; regulation
JEL Codes: I11; J44
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| Increased NP and PA supply (Q31) | Minimal overall impact on healthcare market (I11) |
| 10% increase in NP supply (Q31) | 0.003 percentage point decrease in likelihood of office-based visit (I11) |
| NP supply (Q39) | Elasticity of office visits (I11) |
| Favorable regulatory environments for NPs (L38) | Primary care utilization more responsive to NP supply increases (I11) |
| Increased NP supply (Q31) | Positive price change for healthcare visits (I11) |