Since high unit prices are the cornerstone of above-average health care spending in the United States, anything that might lower those unit prices is a welcome idea. Physicians are expensive. Nurse practitioners and physician assistants less so. Encouraging greater use of less expensive clinicians seems like a no-brainer. But non-physicians have been stymied by scope of practice laws pushed by doctors. Since the research very clearly shows that nurse practitioners and physician assistants deliver the same quality as physicians, the only reason for limiting scope of practice is economic–doctors are trying to protect their incomes. And allowing full scope of practice may have population-wide access and quality of care benefits, as indicated in a recent Journal of Health Economics study. (JHE Article) The research focused on mental health services and on whether allowing nurse practitioners to prescribe drugs without physician oversight affected the delivery and outcome of mental health services. In part thanks to drug company marketing, a large percentage of Americans have some mental illness diagnoses and drugs are the most common treatment. We can debate about the value of over-diagnosis, but for people who have real mental illness issues, securing access to good treatment can be difficult. The authors compare self-reported mental health status and mental health related mortality in states that did and did not expand prescribing authority. The time period for the study is long–the researchers examined prescribing authority from 1990 to 2014 and looked at actual prescriptions from 2006 to 2014. They find that states with less restrictive prescribing authority for nurse practitioners experienced an increase in prescriptions for mental health conditions and about a 5% drop in the number of days citizens reported being in poor mental health and an unspecified, and probably uncertain, drop in mental-health related mortality. These declines appeared to be concentrated among poorer and disadvantaged individuals, and nurse practitioners are somewhat more likely than physicians to practice in areas where higher numbers of poor patients reside. This might indicate that the change in prescribing authority expanded access for these populations. While I believe strongly that scope of practice restrictions should be limited to those demonstrated to be necessary by lack of training or by research, and I think that expanding prescribing authority is a good idea and probably beneficial; I am dubious about the adequacy of the link with outcomes purported to be established by this study. Too many other variables and changes occurring during the study period for me to feel there is a conclusive effect of the magnitude shown. But that doesn’t diminish the rationale for expanding prescribing rights.