1. Department of Occupational and Environmental Health; School of Public Health; Wuhan University; Wuhan Hubei 430071 China
2. Department of Social Medicine and Public Health; School of Basic Medical Science; Jiujiang University; Jiujiang Jiangxi China
3. Wuhan Hospital for the Prevention and Treatment of Occupational Diseases; Wuhan 430022 Hubei China
4. Department of School of Public Health; Wuhan University; Wuhan Hubei 430071 China