Table 1 Categories. Definitions and specific criteria for vital status category based on prehospital medical records

Dead on Ambulance Arrival (DOAA)

•Patient found with extensive decay or obviously fatal injuries incompatible with continued life (= lay-bystander signs of death)

or

•Described in the note fields that the patient was found with no signs of life and no vital signs registered or vital signs = 0, no resuscitation attempt, no treatment, and no drugs administered

Out-of-hospital Cardiac Arrest (OHCA)

OHCA was defined according to the Utstein Guidelines [27] as patients where resuscitation was initiated. Patients found with, or developing, OHCA were sub-categorized according to the level of treatment:

Basic Life Support only (OHCA BLS)

•Patient only received basic life support (manual chest compressions and/or rescue breaths, NO defibrillation) – either by bystander only or by any emergency healthcare professional

Advanced treatment (OHCA Advanced treatment)

• Patient received basic life support and defibrillation and/or any advanced treatment (intubation, fluid therapy, adrenalin, mechanical chest compression, oxygen therapy, airway management equipment, or other)

Alive on Ambulance Arrival

Died after prehospital care

• Patients released alive on the scene or brought to a hospital alive without cardiac arrest at any point

End-of-life care

• Patient received only end-of-life care and died on the scene or was released on the scene to end-of-life care, no resuscitation attempted

No clear category

• Prehospital medical record incomplete

or

• Ambulance mission cancelled before arrival at the patient