1. Medical Diagnostics Unit, Thammasat University Hospital, Khlong Nueng, Pathum Thani, Thailand
2. Sleep Center of Thammasat, Thammasat University Hospital, Khlong Nueng, Pathum Thani, Thailand
3. Department of Internal Medicine, Faculty of Medicine, Thammasat University, Khlong Nueng, Pathum Thani, Thailand