Breaking Barriers? Occupational Licensure Compacts and Physician Mobility

• In Event: Supply-Side Healthcare Policies: Effects on Entry, Access, and Quality

Abstract

This paper evaluates the impact of the Interstate Medical Licensure Compact (IMLC) on physician interstate mobility. The IMLC is designed to increase the portability of license for eligible physicians across state borders. Using the Medicare Physician and Other Practitioners by Provider from the Centers for Medicare & Medicaid Services from 2013 to 2022, I estimate the effect of compact membership with extended difference-in-differences approach (Wooldridge, 2021), exploiting quasi-random variation in the timing of compact adoption. The analyses are conducted at two levels: the provider level and the origin-destination pair level, capturing flows between states over time.

The estimated results are mixed. After joining the compact, physicians experience no significant change in levels of interstate move. However, the results show an increase in physician mobility, deviating from state-specific trends. I find little to no impact among non-physician providers, used as a placebo group. State-pair analyses confirm that the observed effects are driven by migration between compact-member states. The results do not hold without controlling for state-specific trends.

Overall interstate mobility remains rare, the magnitude of change is modest, and the estimated flow rates are noisy due to large variance in state physician populations. These findings suggest that while licensing compacts reduce regulatory frictions and benefit some subgroups, broader structural (e.g., aging population) and professional factors (e.g. demand effects by aging population) continue to limit physician mobility. This paper contributes to the occupational licensing and health workforce mobility literature by providing new evidence on the policy’s impact on interstate mobility of physicians.

Author

• Sungbin Park, George Mason University
  Presenting Author