title: Diagnostic accuracy of GPs when using an early-intervention decision support system: a high-fidelity simulation.
abstract: BACKGROUND
  Observational and experimental studies of the diagnostic task have demonstrated the importance of the first hypotheses that come to mind for accurate diagnosis. A prototype decision support system (DSS) designed to support GPs' first impressions has been integrated with a commercial electronic health record (EHR) system.
  
  
  OBJECTIVE
  To evaluate the prototype DSS in a high-fidelity simulation.
  
  
  METHODS
  Within-participant design: 34 GPs consulted with six standardised patients (actors) using their usual EHR. On a different day, GPs used the EHR with the integrated DSS to consult with six other patients, matched for difficulty and counterbalanced.
  
  
  METHODS
  Entering the reason for encounter triggered the DSS, which provided a patient-specific list of potential diagnoses, and supported coding of symptoms during the consultation. At each consultation, GPs recorded their diagnosis and management. At the end, they completed a usability questionnaire. The actors completed a satisfaction questionnaire after each consultation.
  
  
  RESULTS
  There was an 8-9% absolute improvement in diagnostic accuracy when the DSS was used. This improvement was significant (odds ratio [OR] 1.41, 95% confidence interval [CI] = 1.13 to 1.77,P<0.01). There was no associated increase of investigations ordered or consultation length. GPs coded significantly more data when using the DSS (mean 12.35 with the DSS versus 1.64 without), and were generally satisfied with its usability. Patient satisfaction ratings were the same for consultations with and without the DSS.
  
  
  CONCLUSIONS
  The DSS prototype was successfully employed in simulated consultations of high fidelity, with no measurable influences on patient satisfaction. The substantially increased data coding can operate as motivation for future DSS adoption.
authors.affiliation: Department of Surgery and Cancer, Imperial College London, London.
authors.forename: Olga
authors.initials: O
authors.lastname: Kostopoulou
authors.affiliation: Department of Primary Care and Public Health Sciences, King's College London, London.
authors.forename: Talya
authors.initials: T
authors.lastname: Porat
authors.affiliation: Health Research Board Centre for Primary Care Research, Royal College of Surgeons in Ireland, Dublin.
authors.forename: Derek
authors.initials: D
authors.lastname: Corrigan
authors.affiliation: Department of Primary Care and Public Health Sciences, King's College London, London.
authors.forename: Samhar
authors.initials: S
authors.lastname: Mahmoud
authors.affiliation: Department of Surgery and Cancer, Imperial College London, London.
authors.forename: Brendan C
authors.initials: BC
authors.lastname: Delaney
mesh_terms: D000328:Adult; D000368:Aged; D003198:Computer Simulation; D020000:Decision Support Systems, Clinical; D003936:Diagnosis, Computer-Assisted; D003951:Diagnostic Errors / Q000517:prevention & control*; D042241:Early Diagnosis; D057286:Electronic Health Records; D005260:Female; D058006:General Practice / Q000379:methods* / Q000592:standards; D006801:Humans; D008297:Male; D008875:Middle Aged; D058996:Quality Improvement; D012017:Referral and Consultation / Q000592:standards; D015203:Reproducibility of Results; D006113:United Kingdom; D055815:Young Adult
keywords: decision support systems; diagnosis; diagnostic accuracy; diagnostic errors; electronic health record; first impressions; general practice