ANN ARBOR—The growing presence of nurse practitioners and physician assistants in medical offices is fueling an ongoing debate with physicians over the best ways to deliver primary care.

The presence of nurse practitioners and physician assistants, and the debate that surrounds it, is the subject of a new study by Peter D. Jacobson, associate professor of health management and policy at the University of Michigan School of Public Health, and colleagues. The article in the new issue of the journal Inquiry examines the role of nurse practitioners (NPs), physician assistants (PAs) and physicians in today’s managed care environment.

The article, “Nurse Practitioners and Physician Assistants as Primary Care Providers in Institutional Settings,” focuses on NPs and PAs at nine health maintenance organizations (HMOs) and multispecialty clinics (MSCs). Physicians were also interviewed, most of whom spoke favorably about NPs and PAs, but some did not.

“In our study we discuss the expanded scope of practice and autonomy of NPs and PAs. It clearly indicates a potential shift of primary care responsibility from physicians to NPs and PAs. Patients should be made aware of who provides primary care and who controls referrals,” Jacobson said.

What exactly is a nurse practitioner? What does a physician assistant do? Better yet, what are they trained to do? How do physicians feel about their role in the health care profession? Those are some of the questions Jacobson addresses.

Nurse practitioners are registered nurses whose formal education and clinical training extend beyond the basic nursing licensure requirements. NPs are trained to diagnose and recommend treatment for common acute illnesses, disease prevention, management of chronic illnesses and a host of other primary care services.

Physician assistants are usually trained by physicians alongside medical students. PAs are awarded a certificate of completion rather than an advanced degree.

“We found that the larger an institution’s managed care population, the greater the NPs’ and PAs’ scope of practice and autonomy. Patients with complex illnesses or multisystem problems usually were referred directly to a physician,” Jacobson said.

Some general duties of NPs and PAs include: providing physical examinations, ordering tests, conducting medical treatment (monitoring diabetes and hypertension), writing prescriptions, providing minor surgical treatment (mole removals) and granting referrals. Both also provide outpatient acute care such as minor trauma and urgent care. Many NPs and PAs said they also provide well care, particularly for children’s and women’s health. That includes annual Pap smears and breast examinations.

NPs and PAs said they treated the whole person, including diagnosis and treatment, but with a focus on health care prevention and education. Many said they take more time with patients than physicians.

Whether an NP or PA can issue prescriptions largely depends on whether they work for an HMO or an MSC. Those who worked for HMOs had greater prescriptive authority than NPs or PAs who work for MSCs, although some MSCs were flexible in their rules.

Jacobson found that the duties of NPs and PAs were largely determined by the procedures of individual clinics and departments where they worked.

There are limits to what NPs and PAs are authorized to do. They do not treat patients with complicated illnesses and although they are permitted by law, the institutions in this study did not permit NPs and PAs to admit patients to hospitals.

How well do NPs and PAs work with physicians? Most physicians said they considered them peers. One physician said, “PAs do everything I do. I consult with them as much as they consult with me. We see ourselves as colleagues.”

But a small minority of physicians did not view their working relationships with NPs and PAs as positively. They were critical of NP and PA skills and, in general, the quality of care given. They were also concerned about inadequate referrals to physicians and they were also uncomfortable with the idea of being responsible for patients seen by NPs and PAs without having seen the patient themselves.

“Our interviews indicated that the level of physician acceptance was a critical factor in determining how extensive the NPs’ and PAs’ practice could be,” Jacobson said.

Alternative policies are currently under consideration by managed care organizations to increase the number of NPs and PAs. Doing so may slow the growth of hiring new primary care physicians, Jacobson said.

The study was co-authored by Louise E. Parker, senior psychologist at the Institute of Work Psychology, University of Sheffield, United Kingdom; and Ian D. Coulter, a health consultant at the RAND Corp., a public policy research institution in Santa Monica, Calif., and a professor of public health dentistry, School of Dentistry, University of California at Los Angeles.

This study was done in cooperation with the RAND Health Sciences Program. The study was funded by the Physician Payment Review Commission, a commission that advises Congress on Medicare payment policies.

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