NPs vs MDs: Diagnostic Reasoning in Complex Cases

Tom G. Bartol, NP


August 04, 2015

Nurse Practitioners Versus Doctor Diagnostic Reasoning in a Complex Case Presentation to an Acute Tertiary Hospital: A Comparative Study

Pirret AM, Neville SJ, La Grow SJ
Int J Nurs Stud. 2015;52:716-726

An Exercise in Diagnostic Reasoning

This study from New Zealand examines the diagnostic reasoning of nurse practitioners (NPs) and physicians in response to a complex inpatient case presentation, using a "think aloud" protocol. The case study was a real patient presenting to a tertiary care facility: a 67-year-old man with a worsening productive cough, left-sided chest pain, and a 2-week history of flu-like symptoms. He had coexisting type 2 diabetes, hypertension, and hyperlipidemia. Further subjective and objective data were given, including imaging results.

The primary outcome was the number of correct diagnoses, problems, and actions identified by the participants. "Diagnosis" refers to labeling of the disease or illness, and "problem" means abnormal findings or problems needing intervention. Correct responses were determined by an expert panel.

The goal was to have 30 NPs and 30 physicians complete the exercise, but the investigators were able to recruit only 16 physicians from those completing postgraduate specialty training programs. All clinicians worked in the areas of primary care, gerontology, emergency care, cardiology, respiratory disease, or palliative care. The largest number were from primary care.

The correct diagnosis was made by 61.9% of physicians and 54.7% of NPs. The correct problem was identified by 56.3% of physicians and 53.3% of NPs. The correct actions were identified by 34.4% of the physicians and 35.8% of the NPs. None of the differences were statistically significant. Participants who took longer to complete the case scenario were more accurate in their responses.

The study concluded that NP diagnostic reasoning in a complex case scenario compared favorably with that of physicians.


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