1. Department of Rehabilitation Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
2. Swiss Paraplegic Research, Nottwil, Switzerland
3. Department of Medical Services, Sirindhorn National Medical Rehabilitation Institute, Ministry of Health, Nonthaburi, Thailand
4. Department of Rehabilitation Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
5. Department of Health Sciences and Medicine, University of Lucerne, Lucerne, Switzerland