Souls on board: helicopter emergency medical services and safety.
Isakov
Alexander P
AP
D000060:Accidents, Aviation / Q000401:mortality / Q000517:prevention & control / Q000706:statistics & numerical data; D017732:Air Ambulances; D000401:Aircraft; D004632:Emergency Medical Services; D006801:Humans; D012189:Retrospective Studies; D012307:Risk Factors; D012449:Safety; D014481:United States; D014887:Weather