[1] Natl Cheng Kung Univ, Coll Med, Dept Publ Hlth, Tainan 701, Taiwan
[2] Buddhist Tzu Chi Gen Hosp, Dept Phys Med & Rehabil, Taipei, Taiwan
[3] Tzu Chi Univ, Dept Med, Hualien, Taiwan
[4] Univ Leeds, Div Biostat, Ctr Biostat & Epidemiol, Leeds Inst Genet Hlth & Therapeut, Leeds, W Yorkshire, England
[5] Univ Leeds, Dept Periodontol, Leeds Dent Inst, Leeds, W Yorkshire, England
[6] Natl Cheng Kung Univ Hosp, Dept Environm & Occupat Med & Internal Med, Tainan 70428, Taiwan
[7] Natl Taiwan Univ, Inst Occupat Med & Ind Hyg, Taipei 10764, Taiwan