1. Consultant Anesthetist, National Hospital for Neurology and Neurosurgery, and the Royal Free Hospital, London, United Kingdom.
2. Specialist Registrar in Anesthesia.
3. Assistant Professor of Anesthesia and Critical Care Medicine, Sunnybrook and Women's College Health Sciences Centre, Toronto, Canada.
4. Medical Statistician, Medical Statistics Unit, Research and Development Directorate, University College London Hospitals NHS Trust, London, United Kingdom.
5. Professor of Surgical Neurology, National Hospital for Neurology and Neurosurgery.