1. Muhimbili University College of Health Sciences, Dar es Salaam, Tanzania
2. Evidence for Population Health Unit, School of Epidemiology and Health Sciences, The Medical School, University of Manchester, Oxford Road, Manchester M13 9PT
3. School of Population and Health Sciences, The Medical School, University of Newcastle upon Tyne
4. School of Clinical Medical Sciences. The Medical School, University of Newcastle upon Tyne, UK
5. Facultyof Medicine and Biomedical Sciences, University of Yaoundél, Cameroon
6. Adult Morbidity and Mortality Project, Dar es Salaam, Tanzania
7. department of Diabetes and Metabolic Disease, St Louis Hospital, Paris 10, France