1. Ifakara Health Institute, Dar es Salaam, Tanzania
2. Department of Population Studies, London School of Hygiene and Tropical Medicine, London, UK
3. Malawi Epidemiology and Intervention Research Unit, Karonga, Malawi
4. Africa Health Research Institute, Durban, South Africa
5. Management Sciences for Health, Lilongwe, Malawi
6. Department of Epidemiology and Biostatistics, Kilimanjaro Christian Medical University College, Moshi, Tanzania