Healthcare Credentials Explained: MD, DO, NP, PA and Other Clinicians

Physicians: MD and DO

According to the Bureau of Labor Statistics Occupational Outlook Handbook, physicians may hold a Doctor of Medicine (MD) or a Doctor of Osteopathic Medicine (DO) degree. Both use the same methods of treatment, including medications and surgery. DOs place additional emphasis on the musculoskeletal system, preventive medicine and whole-person care.

Education and training

BLS describes the usual path as a bachelor's degree, a degree from a medical school, which takes about 4 more years, and 3 to 9 years of internship and residency training, depending on the specialty. Some physicians then complete a fellowship for further subspecialty training.

Licensing

Every state requires physicians to be licensed. BLS notes that candidates must graduate from medical school, complete residency training and pass a national licensing exam: the United States Medical Licensing Examination (USMLE) for MDs or the Comprehensive Osteopathic Medical Licensing Examination (COMLEX-USA) for DOs. The license is issued by the state, and a physician needs one in each state where they practice.

Board certification

Board certification is voluntary and is not required for a license. It shows that a physician met the standards of a specialty board. MDs and DOs can be certified by member boards of the American Board of Medical Specialties, which you can check on Certification Matters; DOs can also be certified by osteopathic boards; the American Osteopathic Association points patients to DocInfo.org to check a DO's board certification.

Nurse practitioners (NP)

Nurse practitioners are advanced practice registered nurses (APRNs). The BLS handbook entry for APRNs explains that they must be registered nurses, hold at least a master's degree in their specialty role, and pass a national certification exam, along with state licensing as an APRN. Some hold a Doctor of Nursing Practice (DNP) degree.

NPs diagnose and treat conditions, order tests and prescribe medications. How independently they may do this depends on the state: some states let NPs practice on their own, others require a collaborative or supervisory agreement with a physician.

Checking an NP license

NP licenses are issued by state boards of nursing. You can check them with Nursys QuickConfirm, a free lookup of license and discipline status from participating boards of nursing, or on the board's own site.

Physician assistants (PA)

The BLS handbook entry for physician assistants says PAs typically need a master's degree from a PA program, every state and the District of Columbia requires them to be licensed, and licensing requires passing a qualifying exam. That exam is the Physician Assistant National Certifying Examination (PANCE), which, as NCCPA explains on its certification page, is open to graduates of an approved entry-level PA program.

PAs examine patients, diagnose, order tests, treat and prescribe medications. They work with physicians and other providers under arrangements that each state defines, such as supervision or collaboration agreements.

"PA-C" means the PA currently holds national certification from the National Commission on Certification of Physician Assistants. You can check it with the NCCPA verification tool. Certification and the state license are separate.

Other clinicians you may see in a directory

• Dentists (DDS or DMD): BLS notes in its dentists entry that the Doctor of Dental Surgery and Doctor of Dental Medicine are equivalent degrees. Dentists are licensed by the state.
• Podiatrists (DPM): Doctors of Podiatric Medicine diagnose and treat conditions of the foot, ankle and lower leg, as described in the BLS podiatrists entry, and are licensed by the state.
• Chiropractors (DC): Doctors of Chiropractic treat problems of the neuromusculoskeletal system, such as back and neck pain, according to the BLS chiropractors entry, and are licensed by the state.
• Optometrists (OD): Doctors of Optometry examine the eyes, diagnose and treat vision problems and manage some eye diseases, as described in the BLS optometrists entry. They are different from ophthalmologists, who are physicians (MD or DO).
• Licensed clinical social workers (LCSW): LCSW is a license, not a degree. BLS explains in its social workers entry that clinical social workers need a master's degree in social work, supervised clinical experience after the degree, and a state clinical license.
• Registered nurses (RN), physical therapists (PT or DPT), pharmacists (PharmD) and others also have NPIs and appear in directories. Each is licensed by its own state board.

How credentials appear in NPI records

When providers apply for an NPI, they enter a credential in a free-text field, and the NPI Registry shows it as entered. That is why the same degree can appear as "MD", "M.D." or "MD, FACC". CMS does not check this field against schools, licenses or certifying bodies.

On T-MedInfo, we expand common abbreviations to their full names so that "FNP-BC" is shown as "Family Nurse Practitioner (Board Certified)". The expansion only explains the letters the provider entered. It does not mean we confirmed the certification.

A second clue is the taxonomy code in the NPI record, which describes the provider type, such as "Nurse Practitioner" or "Physician Assistant". Our taxonomy guide explains how to read it. Like the credential field, it is chosen by the provider.

What credentials do and do not tell you

Credentials tell you about a clinician's training path and the kind of license they need. They do not tell you:

• whether the license is active today: check the state board, as described in our license guide;
• whether the clinician is board certified: board certification is not shown by the degree letters and is not in NPI data;
• how much experience they have with your condition: ask at the visit;
• what they may do without a physician in your state, for NPs and PAs: state law and the practice's policies decide.

Choosing between types of clinicians

Many practices have physicians, NPs and PAs working as a team, and you may see different clinicians at different visits. It is reasonable to ask who will see you, what their role is and when a physician will be involved. For complex or specialized care, ask whether the practice will involve a specialist physician. Our guide to choosing a specialist has a list of questions for the first visit.