1. Department of Public Health, The University of Sydney, NSW 2006
2. Public Health Unit, Northern Sydney Area Health Service, Hornsby & Ku-ring-gai District Hospital, Palmerston Road, Hornsby 2077, Australia
3. Department of Emergency Medicine, Royal North Shore Hospital, St Leonards 2065, NSW
4. Department of Cardiology, Royal North Shore Hospital, St Leonards 2065, NSW