title: The difficult medical emergency call: A register-based study of predictors and outcomes.
abstract: BACKGROUND
  Pre-hospital emergency care requires proper categorization of emergency calls and assessment of emergency priority levels by the medical dispatchers. We investigated predictors for emergency call categorization as "unclear problem" in contrast to "symptom-specific" categories and the effect of categorization on mortality.
  
  
  METHODS
  Register-based study in a 2-year period based on emergency call data from the emergency medical dispatch center in Copenhagen combined with nationwide register data. Logistic regression analysis (N = 78,040 individuals) was used for identification of predictors of emergency call categorization as "unclear problem". Poisson regression analysis (N = 97,293 calls) was used for examining the effect of categorization as "unclear problem" on mortality.
  
  
  RESULTS
  "Unclear problem" was the registered category in 18% of calls. Significant predictors for "unclear problem" categorization were: age (odds ratio (OR) 1.34 for age group 76+ versus 18-30 years), ethnicity (OR 1.27 for non-Danish vs. Danish), day of week (OR 0.92 for weekend vs. weekday), and time of day (OR 0.79 for night vs. day). Emergency call categorization had no effect on mortality for emergency priority level A calls, incidence rate ratio (IRR) 0.99 (95% confidence interval (CI) 0.90-1.09). For emergency priority level B calls, an association was observed, IRR 1.26 (95% CI 1.18-1.36).
  
  
  CONCLUSIONS
  The results shed light on the complexity of emergency call handling, but also implicate a need for further improvement. Educational interventions at the dispatch centers may improve the call handling, but also the underlying supportive tools are modifiable. The higher mortality rate for patients with emergency priority level B calls with "unclear problem categorization" could imply lowering the threshold for dispatching a high level ambulance response when the call is considered unclear. On the other hand a "benefit of the doubt" approach could hinder the adequate response to other patients in need for an ambulance as there is an increasing demand and limited resources for ambulance services.
  
  
  CONCLUSIONS
  Age, ethnicity, day of week and time of day were significant predictors of emergency call categorization as "unclear problem". "Unclear problem" categorization was not associated with mortality for emergency priority level A calls, but a higher mortality was observed for emergency priority level B calls.
authors.affiliation: Emergency Medical Services Copenhagen, University of Copenhagen, Telegrafvej 5, 2750, Ballerup, Denmark. tpm@dadlnet.dk.
authors.forename: Thea Palsgaard
authors.initials: TP
authors.lastname: Møller
authors.affiliation: National Institute of Public Health, University of Southern Denmark, Øster Farimagsgade 5A, 1353, København K, Denmark.
authors.forename: Thora Majlund
authors.initials: TM
authors.lastname: Kjærulff
authors.affiliation: Emergency Medical Services Copenhagen, University of Copenhagen, Telegrafvej 5, 2750, Ballerup, Denmark.
authors.forename: Søren
authors.initials: S
authors.lastname: Viereck
authors.affiliation: Copenhagen Academy for Medical Education and Simulation, University of Copenhagen, Herlev Ringvej 75, 2730, Herlev, Denmark.
authors.forename: Doris
authors.initials: D
authors.lastname: Østergaard
authors.affiliation: Emergency Medical Services Copenhagen, University of Copenhagen, Telegrafvej 5, 2750, Ballerup, Denmark.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Folke
authors.affiliation: National Institute of Public Health, University of Southern Denmark, Øster Farimagsgade 5A, 1353, København K, Denmark.
authors.forename: Annette Kjær
authors.initials: AK
authors.lastname: Ersbøll
authors.affiliation: Emergency Medical Services Copenhagen, University of Copenhagen, Telegrafvej 5, 2750, Ballerup, Denmark.
authors.forename: Freddy K
authors.initials: FK
authors.lastname: Lippert
mesh_terms: D000293:Adolescent; D000328:Adult; D000071822:Emergency Medical Dispatcher; D004632:Emergency Medical Services; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D011787:Quality of Health Care; D012042:Registries; D014218:Triage / Q000592:standards*; D055815:Young Adult
keywords: Emergency call; Emergency medical dispatching; Emergency medical services; Pre-hospital emergency care; Triage