1. Department of Emergency Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
2. Chang Gung University College of Medicine, Taoyuan, Taiwan.
3. Department of Emergency Medicine, Veterans General Hospital, Taipei, Taiwan.
4. Institute of Environmental and Occupational Health Science, National Yang-Ming University, Taipei, Taiwan.
5. Resource Center for Clinical Research, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
6. Department of Emergency Medicine, National Yang-Ming University Hospital, Yilan, Taiwan.