1. Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
2. Divisions of Neurology and Nephrology, Department of Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
3. Department of Neurology, Hospital Pulau Pinang, 10990 Penang, Malaysia
4. Division of Neurology, Department of Medicine, Hospital Universiti Kebangsaan Malaysia, 56000 Kuala Lumpur, Malaysia
5. Division of Neurology, Department of Medicine, Hospital Sultanah Nur Zahirah, 20400 Kuala Terengganu, Malaysia
6. Department of Neurology, Hospital Kuala Lumpur, 50586 Kuala Lumpur, Malaysia
7. Department of Medicine, Hospital Seberang Jaya, 13700 Penang, Malaysia
8. Department of Clinical Research and Neurology, Singapore General Hospital, Singapore 169608