title: Nurse practitioners versus doctors diagnostic reasoning in a complex case presentation to an acute tertiary hospital: a comparative study.
abstract: BACKGROUND
  Nurse practitioners perform a diagnostic role previously delivered by doctors. Multiple studies demonstrate nurse practitioners are as effective as doctors when managing chronic conditions and minor illnesses and injuries. No studies have focused on how nurse practitioners compare to doctors in their management of complex cases presenting for the first time.
  
  
  OBJECTIVE
  This study assessed how nurse practitioners' diagnostic reasoning abilities when managing a complex case compared to those of doctors'?
  
  
  METHODS
  A comparative research design.
  
  
  METHODS
  Purposeful sampling recruited 30 nurse practitioners and 16 doctors working in multiple specialties in New Zealand. All doctors were completing postgraduate specialist training programmes. Specialties included older adults, emergency care, primary health care/general practice, cardiology, respiratory and palliative care.
  
  
  METHODS
  A complex case scenario assessed by an expert panel and think aloud protocol was used to assess diagnostic reasoning abilities. The ability of 30 nurse practitioners to determine diagnoses, identify the problem, and propose actions was compared to that of 16 doctors. Correct responses were determined by an expert panel. Data gained from the case scenario using think aloud protocol were quantified for analysis.
  
  
  RESULTS
  61.9% of doctors identified the correct diagnoses, 56.3% the problem and 34.4% the actions as determined by the expert panel. This compares to 54.7% of nurse practitioners identifying the correct diagnoses, 53.3% the problem and 35.8% the actions. Analysis revealed no difference between these groups (diagnoses 95% CI: -1.76 to -0.32, p=0.17, problem χ(2)=0.00, p=1.0, or actions 95% CI: -1.23 to 1.58, p=0.80).
  
  
  CONCLUSIONS
  Nurse practitioners' diagnostic reasoning abilities compared favourably to those of doctors in terms of diagnoses made, problems identified and action plans proposed from a complex case scenario. In times of global economic restraints this adds further support to alternative models of care.
authors.affiliation: School of Nursing, College of Health, Massey University, New Zealand; Critical Care Complex, Middlemore Hospital, Auckland, New Zealand. Electronic address: A.M.Pirret@massey.ac.nz.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Pirret
authors.affiliation: School of Nursing, College of Health, Massey University, New Zealand.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Neville
authors.affiliation: College of Health, Massey University, New Zealand.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: La Grow
mesh_terms: D003933:Diagnosis; D005260:Female; D006801:Humans; D008297:Male; D009520:New Zealand; D009722:Nurse Practitioners; D010820:Physicians; D024382:Professional Role; D062606:Tertiary Care Centers
keywords: Complex case; Diagnostic accuracy; Diagnostic reasoning; Nurse practitioners; Registrars