2-2 Yamadaoka, Suita-shi, Osaka, 565-0871 Japan.
Department of Social Medicine, Graduate School of Medicine, Osaka University, Unit of Advanced clinical epidemiology
Tel:+81-6-6879-3911 Fax:+81-6-6879-3919
Mail:r.sakaniwa@pbhel.med.osaka-u.ac.jp