1. From the Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia (J.E.B., L.S., J.F.); Alfred Hospital, Melbourne, Victoria, Australia (J.E.B.); Curtin University, Perth, Western Australia, Australia (J.E.B., J.F.); Ambulance Victoria, Melbourne, Victoria, Australia (B.B.); and St John Ambulance, Perth, Western Australia, Australia (J.F.).