1. Faculty of Clinical Sciences, University of Ilorin, Ilorin, Nigeria
2. Department of Medicine and Surgery, Obafemi Awolowo University Teaching Hospital, Ife, Nigeria
3. Department of Medicine and Surgery, University of Ibadan, Ibadan, Nigeria
4. Johns Hopkins Bloomberg School of Public Health, Washington, DC
5. Department of Medicine and Surgery, Ladoke Akintola University of Technology Teaching Hospital, Ogbomoso, Nigeria.