Kekalih A., Department of Community Medicine, Faculty of Medicine, Universitas Indonesia, Jakarta, 10320, Indonesia; Adi N.P., Department of Community Medicine, Faculty of Medicine, Universitas Indonesia, Jakarta, 10320, Indonesia, Department of Occupational Health Practice and Management, Institute of Industrial and Ecological Sciences, University of Occupational and Environmental Health, Japan. Yahatanishi-ku, Kitakyushu, 807-8555, Japan; Soemarko D.S., Department of Community Medicine, Faculty of Medicine, Universitas Indonesia, Jakarta, 10320, Indonesia