LETTERS Health Outcomes Among Patients Treated by Nurse Practitioners or Physicians To the Editor: The study by Dr Mundinger and colleagues 1 compared the health outcomes of patients treated by nurse prac- titioners to those treated by physicians in primary care set- tings that were similar in terms of responsibilities and patient panels. There was no description of the training of either the physicians or the nurses in the study, other than that they were all faculty members. The authors state, “The combination of authority to prescribe drugs, direct reimbursement from most payers, and hospital admitting privileges creates a situation in which nurse practitioners and primary care physicians can have equivalent responsibilities.” This combination does not in- clude core elements of medical care such as evaluation, diag- nosis, and treatment of undifferentiated patients. Patients with previously diagnosed and treated asthma, diabetes, and hyper- tension could be cared for successfully in a limited time frame by a person with less training than a physician. Each of these conditions has very clear treatment guidelines. The most troublesome aspect of the study is the outcome mea- sure. Although the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) is a well-established measure of health sta- tus, it assesses only self-reported perception of health. Further- more, the sensitivity of the SF-36 for detecting longitudinal change within patients has been questioned. 2 Patient satisfaction may be important but in itself is not a measure of the ability to provide many of the complicated aspects of patient diagnosis and care. In the accompanying Editorial, 3 Dr Sox states that the study has strong internal but weak external validity, and thus the con- clusions of this study cannot be generalized. They are highly limited to this particular patient population and clinical struc- ture and the relatively brief period of this study. Bruce Bagley, MD American Academy of Family Physicians Leawood, Kan 1. Mundinger MO, Kane RL, Lenz ER, et al. Primary care outcomes in patients treated by nurse practitioners or physicians: a randomized trial. JAMA. 2000;283: 59-68. 2. Edelman D, Williams GR, Rothman M, Samsa GP. A comparison of three health status measures in primary care outpatients. J Gen Intern Med. 1999;14:759- 762. 3. Sox HC. Independent primary care practice by nurse practitioners. JAMA. 2000; 283:106-107. To the Editor: The article by Dr Mundinger and colleagues 1 con- cluded that nurse practitioners with the “same authority, respon- sibilities, productivity and administrative requirements, and pa- tient population” had “comparable outcomes to primary care physicians.” However, its implication that primary care given in- dependently by nurse practitioners is equivalent to that pro- vided by physicians cannot be concluded from this study. First, patients were followed up for only 6 months, too brief an interval to accurately assess the quality of care. In primary care, the typical patient-physician relationship spans a much longer period. This ongoing relationship, which is the hall- mark of primary care, demands considerable skill as patients’ medical conditions evolve, progress, and, ideally, stabilize and improve. The continuity of primary care is in stark contrast with the 0 to 2 ambulatory visits noted in 60% of the study sample. Second, the mean age of the patients in this sample was 45.9 years, with 76.8% women and 90.3% of Hispanic background. This sample certainly is not representative of most primary care practice. As mentioned in the accompanying Editorial, 2 health outcomes in this young, predominantly Hispanic population are usually good. Finally, no information was given about the physicians’ or nurse practitioners’ level of experience. This information is ex- tremely pertinent; cumulative clinical experiences reinforce and hone physicians’ knowledge base, thereby significantly im- proving their effectiveness, efficiency, and competency. In my own experiences as a second-year resident in internal medi- cine, I am definitely more competent in the ambulatory set- ting than I was as an intern. There is an ongoing learning curve for physicians in the primary care setting. Kirk M. Chan-Tack, MD University of Missouri, Columbia 1. Mundinger MO, Kane RL, Lenz ER, et al. Primary care outcomes in patients treated by nurse practitioners or physicians: a randomized trial. JAMA. 2000;283: 59-68. 2. Sox HC. Independent primary care practice by nurse practitioners. JAMA. 2000; 283:106-108. To the Editor: Dr Mundinger and colleagues 1 provide an ex- cellent comparison of the care provided by nurse practition- ers and primary care physicians from several perspectives. In considering their work, though, one must also note cer- tain limitations. Hypertension, asthma, and diabetes, while chronic conditions, do not generally warrant frequent admis- sion to the hospital. Therefore, differences in the rate of emer- gency department use, hospitalization, and mortality may not be evident for some time beyond the 1-year length of the study. Another important limitation is the assessment of the qual- ity of care provided by both groups as reflected by physiologi- GUIDELINES FOR LETTERS. Letters discussing a recent JAMA article should be received within 4 weeks of the article’s publication and should not exceed 400 words of text and 5 references. Letters reporting original research should not ex- ceed 500 words and 6 references. All letters should include a word count. Letters must not duplicate other material published or submitted for publication. Letters will be published at the discretion of the editors as space permits and are subject to editing and abridgment. A signed statement for authorship criteria and respon- sibility, financial disclosure, copyright transfer, and acknowledgment is required for publication. Letters not meeting these specifications are generally not con- sidered. Letters will not be returned unless specifically requested. Also see Instruc- tions for Authors (January 5, 2000). Letters may be submitted by surface mail: Letters Editor, JAMA, 515 N State St, Chicago, IL 60610; e-mail: JAMA-letters @ama-assn.org; or fax (please also send a hard copy via surface mail): (312) 464-5824. Letters Section Editors: Phil B. Fontanarosa, MD, Deputy Editor; Stephen J. Lurie, MD, PhD, Contributing Editor. ©2000 American Medical Association. All rights reserved. (Reprinted) JAMA, May 17, 2000—Vol 283, No. 19 2521