Funding for this research was provided by:
Stiftelsen Norsk Luftambulanse
Received: 7 July 2020
Accepted: 7 October 2020
First Online: 14 October 2020
Ethics approval and consent to participate
: The study was approved by the Committees for Medical and Health Research Ethics in Sweden (reference number: 2016/109) and Finland (reference number: R16031), respectively. In Denmark, application was waved by The Committee for Medical and Health Research Ethics due to the strictly descriptive nature of the study. The Norwegian Committee for Medical and Health Research Ethics defined the study to fall outside their legislation (reference number: 2016/371). According to the approvals from all four countries, the data was obtained without informed consent from patients or their next-of-kin. There was no deviation from regular clinical practice during the study period.
: Not applicable.
: The authors declare the following conflict of interests: AK holds a research position in The Norwegian Air Ambulance Foundation, a non-commercial charity owning The Norwegian Air Ambulance Ltd., which is the contractor of the national air ambulance service in Norway.