1. Department of Rehabilitation and Physical Medicine; Taipei Veteran General Hospital; Taipei Taiwan
2. Department of Medicine; College of Medicine, National Yang Ming University; Taipei Taiwan
3. Department of Emergency Medicine; Chang Gung Memorial Hospital; Keelung Taiwan
4. College of Medicine; Chang Gung University; Taoyuan Taiwan
5. Department of Family Medicine; Chang Gung Memorial Hospital; Taoyuan Taiwan
6. Graduate Institute of Clinical Medical Sciences; College of Medicine; Chang Gung University; Taoyuan Taiwan
7. Department of Emergency Medicine; National Taiwan University Hospital; Yunlin Branch; Douliou Taiwan
8. Department of Epidemiology; Harvard School of Public Health; Boston MA USA