As explained by CMS in the calendar year (CY) 2025 final rule:
Under Medicare Part B, certain types of services, including services incident to physicians’ or practitioners’ professional services, are required to be furnished under specific minimum levels of supervision by a physician or practitioner. For most services furnished by auxiliary personnel incident to the services of the billing physician or practitioner, direct supervision is required.
Outside the circumstances of the PHE, direct supervision requires the immediate availability of the supervising physician or other practitioner, but the professional need not be present in the same room during the service.
We have established this “immediate availability” requirement to mean in-person, physical, not virtual, availability. Through the March 31, 2020, COVID-19 interim final rule with comment period (IFC), we changed the definition of “direct supervision” during the PHE for COVID-19 as it pertains to supervision of diagnostic tests, physicians' services, and some hospital outpatient services, to allow the supervising professional to be immediately available through virtual presence using two-way, real-time audio/video technology, instead of requiring their physical presence.
For 2025, we will continue to continue to define direct supervision to permit the presence and “immediate availability” of the supervising practitioner through real-time audio and visual interactive telecommunications through December 31, 2025.
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