1. Department of Community Health, University of Uyo Teaching Hospital, Uyo, Nigeria;
2. Circulation Health Research Laboratory, College of Health Sciences, University of Abuja, Abuja, Nigeria;
3. Department of Medicine, Federal Medical Centre, Gusau, Nigeria;
4. Chukwuemeka Odumegwu University, Awka, Nigeria;
5. Department of Chemical Pathology, Faculty of Basic Clinical Sciences, University of Abuja, Abuja, Nigeria;
6. Department of Medicine, Federal Teaching Hospital, Gombe, Nigeria;
7. Department of Medicine, University of Uyo, Uyo, Nigeria;
8. Department of Human Physiology, Faculty of Basic Medical Sciences, University of Abuja, Abuja, Nigeria;
9. Department of Medicine, University College Hospital, Ibadan, Nigeria;
10. Department of Medicine, Federal Teaching Hospital, Abakiliki, Nigeria