title: Factors influencing diagnostic decision-making.
abstract: BACKGROUND
  Identifying influences on diagnostic decisions is important because diagnostic errors often have far-reaching consequences for an individual's future within the workforce and their eligibility for Accident Compensation Corporation-funded treatment. Most investigations of factors biasing decision making have used quantitative techniques rather than qualitative methods.
  
  
  OBJECTIVE
  To identify factors influencing GPs' diagnostic decision-making and to develop a valid questionnaire to determine the desirability and importance of each factor's influence.
  
  
  METHODS
  Focus groups and the Delphi method were combined with Rasch analysis to identify factors influencing GPs' diagnostic decision-making and then examine the strength and stability of ratings of the factors' desirability and importance.
  
  
  RESULTS
  Thirty-nine factors were identified. Factors demonstrating high stability but no consensus included the importance of evidence-based medicine, the potential ramifications of a diagnosis, and the desirability of medicolegal issues. Factors for which there was disagreement in the first Delphi round but consensus in the second round included the importance of patient advocacy/support groups and the desirability of examination findings. Rasch analysis indicated that the questionnaire was close to the model (88.6% and 86.2% of variance in the ratings of importance and desirability explained).
  
  
  CONCLUSIONS
  Participants readily identified factors influencing GPs' diagnostic decision-making. Their ratings did not appear to support a prescriptive model of medicine, yet two cornerstones of prescriptive medicine, clinical information and probability of disease, were rated as highly desirable and important.
authors.affiliation: Human Factors Group, Department of Surgery, The University of Auckland, PB 92019, Auckland, New Zealand. k.callaghan@auckland.ac.nz
authors.forename: Kathleen S N
authors.initials: KS
authors.lastname: Callaghan
mesh_terms: D003697:Delphi Technique; D003933:Diagnosis; D005260:Female; D017144:Focus Groups; D058005:General Practitioners; D006801:Humans; D008297:Male; D009520:New Zealand; D011795:Surveys and Questionnaires