1. Prehospital, Resuscitation and Emergency Care Research Unit, Curtin School of Nursing, Curtin University, Perth, WA, Australia
2. Discipline of Emergency Medicine, Medical School, The University of Western Australia, Perth, WA, Australia
3. St John Western Australia, Belmont, WA, Australia
4. School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
5. Emergency Department, Fiona Stanley Hospital, Murdoch, WA, Australia