The U.S. is facing a deficit of primary care that some advocates want to fill by expanding the responsibilities of nurse practitioners. Former South Dakota Sen. Tom Daschle and David Hebert of the American Association of Nurse Practitioners wrote last month in The Inquirer in support of having NPs in primary care as a part of “bipartisan” health reform. While nurse practitioners are vital members of the health-care team, they are not meant to replace physicians. To expand their role in this way could prove detrimental and dangerous for patients.

Recently, in New Jersey, a bill that would allow nurse practitioners to prescribe medication and treat without a physician was defeated for safety concerns. We also disagreed with this bill, because the education, regulations, and training required to practice are very different between physicians and nurse practitioners.

The research does not, in fact, show that nurse practitioners can provide comparable care to physicians. Many of the studies cited to support NPs providing direct primary care have always occurred in settings where nurse practitioners were working under physician supervision. For example, one study sampled Medicare patients at random, yet in more than half of the United States, nurse practitioners are required to see Medicare patients under the supervision of an attending physician, meaning they’re not practicing independently.

We have yet to see a reliable study with a large, diverse sample size and similar complexity of patients that compares physicians and nurse practitioners practicing independently to assess whether NPs can effectively provide primary care for patients over the course of a lifetime.

Also, while the number of nurse practitioners has grown exponentially, workforce data shows that states that have allowed independent practice have not seen an increase of nurse practitioners practicing in underserved areas. Instead, independent nurse practitioners end up working in the exact same locations as physicians. In addition, surveys and health-care experts suggest that many nurse practitioners are foregoing primary care, instead opting to work in specialty offices and/or administrative roles.

Nurse practitioners are also unlikely to save the health system money. In fact, one of the first studies to examine nurse practitioners, published in 1974, suggested increased health-care costs due to a much higher utilization of care services compared with physicians. In the decades since this study was published, research has indicated that nurse practitioners order more unnecessary diagnostic tests and prescriptions, including antibiotics, and have lower quality referrals to specialists than physicians do.

The reality is, educational requirements for nurse practitioners are a fraction of that required of physicians. For example, a newly trained primary care physician has approximately 20,000 clinical hours between medical school and residency before they practice. Nurse practitioners can practice with as few as 500 clinical hours.

More concerning is that the quality of newer nurse practitioner programs has been called into question. Unlike medical school, some nursing graduate programs boast 100% acceptance rates, are completely online, and lack the clinical experience standards required of physician trainees.

While advocates of expanded NP roles describe a physician shortage, they fail to note that America is already facing a shortage of nurses. By encouraging more nurses to move into a “medical provider” role, nurse practitioner independence would have a negative impact on an already short supply of bedside nurses.

While we agree that Americans deserve access to high-quality, affordable health care, nurse practitioner independence is not the “low-hanging fruit” of reform it appears to be. Legislators should focus instead on increasing the supply of physicians — starting with preventing the closure of residency training programs like the one at Hahnemann University Hospital in Philadelphia, which disrupted the training of nearly 600 Pennsylvania physicians. They can do so by backing legislation to expand graduate medical education with more residency program slots. The growth of medical schools in the U.S. has far outpaced that of the residency training programs necessary for medical school graduates to practice.

It’s time to double down on supporting, not replacing, physicians.

Rebekah Bernard and Purvi Parikh are board members of Physicians for Patient Protection, a grassroots organization of practicing and retired physicians, resident physicians, and medical students.