1. Department of Public Health, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon.
2. Department of Public Health, Faculty of Medicine and Biomedical Sciences, University of Yaounde I, Yaounde
3. Department of Odonto-Stomatology & Maxillo-Facial Surgery, Faculty of Medicine & Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon