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MD, DO, PA, NP: What do the letters mean?


MD, DO, PA, NP: What do the letters mean?

If you visit the emergency department or schedule a medical appointment, your care may be led by a variety of care providers with different letters behind their names.
So what’s the difference between a medical doctor (MD), doctor of osteopathic medicine (DO), physician assistant (PA) and nurse practitioner (NP)?
Each role requires various levels of training and education, including certifications and clinical rotations, some more stringent than others, but all bring their own unique strengths and expertise to patient care.
“Our team works well together,” said Catherine Gillespie, lead physician assistant in the emergency department at Tidelands Waccamaw Community Hospital. “Everybody knows their jobs, and we all share a common goal of providing excellent care.”

MDs and DOs

Doctors of medicine (MDs) and doctors of osteopathy (DOs) undergo the most extensive training of any medical professionals and can be found in hospitals, clinics and other health care settings. Both complete lengthy education, upwards of two decades or more, typically including a four-year bachelor’s degree, four years of medical school, and three to seven years of residency training after receiving their medical degrees. They must also obtain medical licenses in the states where they provide care and participate in continuing education. Many also seek board certification in their respective specialties and complete recertification exams every seven to 10 years.

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The MD and DO degrees are recognized as legally equivalent by state and federal agencies and by post-graduate training programs.
Doctors of osteopathic medicine traditionally receive training in a holistic approach to patient care, including specialized training in musculoskeletal and neurological systems that enables them to offer osteopathic manipulative treatments.

Physician assistants and nurse practitioners

Physician assistants and nurse practitioners are among the fastest-growing health care professions in the U.S. and increasingly serve as front-line care providers responsible for assessing injuries, diagnosing illnesses or caring for wounds.
“My first 10 years of practice, I frequently had to explain who I was and what I could do,” Gillespie says. “It’s such a pleasure now to walk into a room and hear them say, ‘My niece is a PA.’ It has taken 35 years, but I think we’re there.”

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Physician assistants complete a 27-month master’s degree program, which includes a combination of classroom and clinical rotations in a variety of specialties such as obstetrics and gynecology, emergency medicine and psychiatry, according to the American Academy of PAs. They then must pass a national certifying examination and complete 100 hours of continuing education every two years. PAs also must pass a recertification exam every 10 years.
Once certified, physician assistants can diagnose illnesses, develop and manage treatment plans, prescribe medications, perform procedures and more, making them versatile and collaborative. They work with at least one supervising physician.
Much like physician assistants, nurse practitioners can also examine patients, prescribe medications, diagnose illnesses and provide treatment plans.
Most nurse practitioners have earned a nursing degree to become a registered nurse before continuing on to complete a master’s or doctoral degree and advanced clinical training. They must then receive national certification and be certified by the applicable state board before practicing, according to the American Association of Nurse Practitioners.

The difference

So what’s the difference between a physician assistant and a nurse practitioner? Physician assistants, like physicians, train on a medical model that places a greater emphasis on disease pathology, anatomy and the physiology of the human body. Nurse practitioners train on a nursing model that concentrates more heavily on the impact of the diagnosis and treatment on the patient.
Physician assistants train as generalists and can practice in nearly any field with a collaborating physician. Nurse practitioners train in either primary care or acute care, which is often further focused based on the population the individual chooses to serve.

What it means to patients

Advanced practice providers such as physician assistants and nurse practitioners are expected to play an increasingly central role in health care in the coming years due to a forecasted shortage of physicians and a growing need for more primary care professionals as the U.S. population ages.
Together with their attending physicians, the physician assistants and nurse practitioners at Tidelands Health are part of a well-rounded and comprehensive care team that also includes registered nurses and a variety of other care providers.


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