Prehospital triage accuracy in a criteria based dispatch centre

Area of Science:

• Emergency medicine
• Pre-hospital care systems
• Public health

Background:

• Accurate pre-hospital resource allocation is vital for patient outcomes.
• Criteria Based Dispatch (CBD) systems aim to match patient needs with emergency resources.
• Evaluating CBD accuracy is essential for optimizing emergency medical services.

Purpose of the Study:

• To measure the accuracy of a Criteria Based Dispatch (CBD) system.
• To evaluate discrepancies between dispatch priorities and ambulance crew severity assessments.
• To determine over-triage and under-triage rates in a specific CBD implementation.

Main Methods:

• Retrospective study of 2011 pre-hospital missions.
• Utilized National Advisory Committee for Aeronautics (NACA) scores to define dispatch criteria.
• Defined over-triage as L&S dispatches with NACA < 4; under-triage as non-L&S dispatches with NACA > 3.

Main Results:

• Over-triage rate was 78% (L&S dispatches with NACA < 4).
• Under-triage rate was 4.6% (non-L&S dispatches with NACA > 3).
• Sensitivity: 86%, Specificity: 48%, PPV: 21.7%, NPV: 95.4%.

Conclusions:

• The CBD system exhibited high over-triage and low under-triage rates.
• Significant limitations exist in standardizing metrics for dispatch accuracy research.
• Heterogeneity in dispatch and pre-hospital systems complicates universal accuracy assessment.