[1] Univ Occupat & Environm Hlth, Inst Ind Ecol Sci, Dept Clin Epidemiol, Yahatanishi Ku, Kitakyushu, Fukuoka 8078555, Japan
[2] Univ Occupat & Environm Hlth, Inst Ind Ecol Sci, Dept Ergon, Yahatanishi Ku, Kitakyushu, Fukuoka 8078555, Japan
[3] Kinki Univ, Kyushu Sch Engn, Dept Management & Informat Sci, Higashiosaka, Osaka 577, Japan