1. Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts
2. Department of Neurology, Children's Hospital, Boston, Massachusetts
3. Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts
4. Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts
5. Department of Community Health, Muhimbili University College of Health Sciences, Dar es Salaam, Tanzania
6. Maternal and Child Health, Harvard School of Public Health, Boston, Massachusetts