1. Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
2. Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore
3. Department of Emergency Medicine, Singapore General Hospital, Singapore 169608, Singapore
4. Pre-Hospital & Emergency Care Research Centre, Duke-NUS Medical School, Singapore 169547, Singapore
5. Division of Neurosurgery, Department of Surgery, National University Health System, Singapore 119074, Singapore
6. Division of Neurology, Department of Medicine, National University Health System, Singapore 119074, Singapore