1. Department of Social Medicine and Health Management, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P. R. China;
2. Norwich Medical School, Faculty of Medicine and Health Science, University of East Anglia, Norwich, UK;
3. The National Health and Family Commission, Beijing, P. R. China;
4. Department of Occupational & Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P. R. China;
5. Wuhan Hospital for the Prevention and Treatment of Occupational Diseases, Wuhan, P. R. China;
6. Department of Neurology, Tianjin Huanhu Hospital, Tianjin, P. R. China;
7. Xuanwu Hospital, Capital Medical University, Beijing, P. R. China;
8. Department of Science and Education, People's Hospital of Deyang City, Deyang, P. R. China;
9. Department of Neurology, Hebei General Hospital, Shijiazhuang, P. R. China;
10. Shenzhen No. 2 People's Hospital, Shenzhen University, Shenzhen, P. R. China