Considerations when adding a physician extender

Answers in Practice

Rachna Chaudhari

Rachna Chaudhari is the AAD's practice management manager. Her column offers tips in response to common member questions.

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The Academy’s practice management staff frequently receives inquiries related to adding physician extenders to dermatology practices. The 2012 American Academy of Dermatology Association Dermatology Practice Profile Survey noted this trend and found that 40 percent of respondents employed at least one physician extender in their practices, up from 33 percent in 2009. With the current shortage of dermatologists across the country and an expected increase in the employment of physician assistants (PAs) and nurse practitioners (NPs), dermatology practices need to be aware of all the rules and regulations governing the use of physician extenders. The following FAQs guide practices through this process.

What procedures can a physician extender perform in my practice?

Each state has its own laws governing a physician extender’s duties in a medical practice. For a thorough overview of each state’s laws and regulations, please consult the American Academy of Physician Assistants’ resource at or the American Academy of Nurse Practitioners’ website at Additionally, the American Academy of Dermatology has developed a position statement related to the use of physician extenders. The position statement, titled “The Practice of Dermatology: Protecting and Preserving Patient Safety and Quality Care,” is available at This position statement particularly notes that “the optimum degree of dermatologic care is delivered when a dermatologist ... provides direct, on-site supervision to all non-dermatologist personnel.” [pagebreak]

What should I be aware of before hiring a physician extender?

Your practice should first develop a guidebook containing appropriate policies and procedures for a physician extender in your practice. This guidebook should detail the supervising physician’s role and responsibilities, delegation duties, prescriptive authority, and training requirements for the PA or NP. Additionally, this guidebook should detail all diagnostic and therapeutic procedures that can be performed by the PA or NP.

It is also important to have a standard non-physician provider agreement and supervisory/delegation of services/collaborative agreement in place prior to hiring a physician extender. These two agreements will serve as the employment contract for the PA or NP. Model agreements are available in the Academy’s Dermatology Employment Manual; see for information.

How do I recruit a physician extender into my practice?

Advertise an opening throughout the dermatology community by posting ads online or in trade publications. You can visit to post an ad through the Academy. The Society of Dermatology Physician Assistants (SDPA) also has an online job board at and the Dermatology Nurses Association (DNA) has recruitment opportunities for nurse practitioners at [pagebreak]

How do I bill for a physician extender?

Once you have hired a PA or NP into your practice, you will have to determine how best to structure your billing arrangements. Medicare will reimburse a PA or NP at 100 percent of the fee schedule as long as the supervising physician follows “incident-to” guidelines. These guidelines require that the physician meet several criteria:

  1. The services are rendered under the direct supervision of the physician. Direct supervision is defined as the physician being present in the office suite and immediately available to provide assistance.
  2. The services are furnished as an integral, although incidental, part of the physician’s professional services in the course of the diagnosis or treatment of an injury or illness.
  3. The physician must initiate treatment and see the patient at a frequency that reflects his/her active involvement in the patient’s case.
  4. New patients or established patients with new problems can be seen by a physician extender; however this can only be reported under their NPI number and be billed at 85 percent of the fee schedule.
  5. A signed employment arrangement must exist between the physician and the physician extender.
  6. The physician extender must enroll with Medicare Part B to obtain his or her own NPI number.
  7. The physician extender may not provide services outside of his or her own scope of practice based on state-specific law.
  8. The physician cannot hire an extender and bill incident-to if the extender has professional qualifications equaling or exceeding those of the supervising provider. For example, a dermatologist cannot bill the services of a physician in the same practice as incident-to. [pagebreak]

If you determine that your physician extender can meet the incident-to guidelines, you may bill for services under the physician’s NPI. You will be reimbursed as if the physician performed the service. If the visit cannot be classified as incident-to, you will have to bill under the PA or NP’s NPI, and your reimbursement will be at 85 percent of the fee schedule. Please note: very few national insurers allow incident-to billing and your practice will need to check with each individual carrier to determine their rules regarding non-physician practitioner billing. 

Additional resources available

Coding information

For more incident-to coding guidelines, consult the Academy’s 2013 Coding and Documentation for Dermatology Manual, available at

Hiring and training

More information and resources to assist in hiring a PA or NP are available in the Academy’s Dermatology Employment Manual, available at

The Academy’s Medical Student Core Curriculum is an excellent resource to help supervising dermatologists train a PA or NP in dermatology. The core curriculum is available at PAs and NPs working in an AAD fellow’s office may also register to attend the AAD Annual Meeting, which includes several sessions directed specifically to PAs and NPs. Information on the meeting is available at



Additional resources available
Additional resources available