Independent NPs: What’s the Evidence?
As more states change scope-of-practice laws to allow nurse practitioners to practice independently, what does the evidence on health outcomes show?

"...the quality of care is largely equivalent [between patients seen by NPs and physicians]!" the article exhorts. Let's take a closer at the two studies it cites as "evidence", shall we?

Primary Care Outcomes in Patients Treated by Nurse Practitioners or Physicians
Context Studies have suggested that the quality of primary care delivered by nurse practitioners is equal to that of physicians. However, these studies did not measure nurse practitioner practices that had the same degree of independence as the comparison physician practices, nor did previous studie…

Immediately we can point out several flaws:

  • The paper was published in 2000, well before the rise of low-quality diploma mill NP programs in the next decade
  • In terms of "provider attributes", i.e. patients' ratings of the providers' technical skill, personal manner, and time spent with the patient, physicians actually scored slightly higher than NPs
  • Patient health status was assessed using a questionnaire instead of objective measures, and only after six months; rate of healthcare utilization was assessed also at the one year mark. Supposedly, no statistically significant differences were found. But with the exception of patients actively dying from a fast-progressing disease process such as cancer, one could argue that a much longer period is needed to assess the effects of physician vs NP health interventions on long-term health and survival, which, after all, is the ultimate point of primary care.

Even if take these claim of nurse practitioners' noninferiority compared to physicians in primary care, the fact that the percentage of NPs actually practicing in a primary care position may be as low as 25% in some areas, makes it a moot point, doesn't it?

Nurse practitioner independence, health care utilization, and health outcomes - PubMed
Many states allow nurse practitioners (NPs) to practice and prescribe drugs without physician oversight, increasing the number of autonomous primary care providers. We estimate the causal impact of NP independence on population health care utilization rates and health outcomes, exploiting variation …

The 2018 paper by Traczynski and Udalova in the Journal of Health Economics appears much more impressive and well-researched, at least on the surface. But a closer look reveals that it, too, fails to reveal any direct, objective measures to meaningfully differentiate the quality of care provided by physicians versus nurse practitioners. The two pseudo-measures it uses are patient "self-reported health status on a 1–5 scale" and frequency of ED visits, correlated with the timeline of passage of independent practice statutes in various states. As with "patient satisfaction", we all know how meaningful self-reported health scores are...i.e. not at all. The paper notes that the frequency of ED visits dropped after independent practice statues were passed, and optimistically posits that "Individuals may go to the emergency room less when NPs have independence because they have ACS [ambulatory care-sensitive] conditions that become less severe or because the greater availability of primary care leads patients to substitute office-based care for emergency room care." Just as pessimistically, one could posit that patients are no longer going to the ED because their NP noctor completely missed a life-threatening condition and instead told them "everything is fine!"

How about we move to the article's comment section/peanut gallery for a few more, uh, "real-world" examples demonstrating how nurse practitioners provide care that is just as good as a physician's?

Physicians versus midlevel nurse practitioners..."largely equivalent", except for when you kill a patient by completely missing a cancer diagnosis!

For a much more comprehensive body of research that shows why physician-led care is superior from multiple aspects, click here.