Figure 1

Case identification and dispatch systems utilised during the HIRT. The trial case identification system identified patients with possible severe head injury and randomised them to either paramedic only care or additional physician care. The Rapid Launch Trauma Coordinator (RLTC) independently identified some of the same patients and dispatched the GSA HEMS physician team. Therefore teams dispatched to patients consisted of paramedics alone, or in combination with HIRT HEMS, GSA HEMS or both physician services.