Estimating the Primary Care Workforce for Medicare Beneficiaries Using an Activity-Based Approach

Area of Science:

• Health Services Research
• Medical Economics
• Public Health Policy

Background:

• Current primary care workforce estimates rely on potentially inaccurate specialty designations from licensure and surveys.
• Accurate enumeration of primary care providers is crucial for healthcare planning and resource allocation.

Purpose of the Study:

• To estimate the number of physicians, nurse practitioners (NPs), and physician assistants (PAs) providing primary care using an activity-based measure.
• To compare primary care provider estimates based on practice style versus traditional specialty designations.

Main Methods:

• Utilized Medicare fee-for-service (FFS) claims data from 2019 for all US clinicians and their patients.
• Developed three measures to distinguish primary care from specialty clinicians: E&M service presence, care dispersion across ICD-10 chapters, and atypical primary care services.
• Applied parameters to identify primary care providers and compared classifications across provider types.

Main Results:

• 19-22% of physicians with at least 50 Medicare beneficiaries provide primary care.
• 61-68% of medical generalists (family/internal medicine) with a sufficient patient panel provide primary care.
• An estimated 40-45% of NPs and 27-30% of PAs meeting the panel size threshold are primary care providers in FFS Medicare.

Conclusions:

• The number of primary care physicians in FFS Medicare may be lower than conventionally estimated when using a practice style measure.
• Compared to prior estimates, the number of primary care NPs is larger, while the number of primary care PAs is similar.
• Activity-based measures provide a more nuanced understanding of the primary care workforce composition.