Joanne Cobbett1,2, Viet Tran3,4, Kimberly Humphrey5. 1. Emergency Department, Southern District Health Board, Dunedin, New Zealand. 2. Dunedin School of Medicine, University of Otago, Dunedin, New Zealand. 3. Emergency Department, Royal Hobart Hospital, Hobart, Tasmania, Australia. 4. School of Medicine, University of Tasmania, Hobart, Tasmania, Australia. 5. Emergency Department, Royal Adelaide Hospital, Adelaide, South Australia, Australia.