1. MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt)School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
2. Community Medicine DepartmentCollege of Medical Sciences, University of Calabar, Cross River State, Nigeria
3. INDEPTH Network Accra, Ghana
4. Umeå Centre for Global Health Research, Epidemiology and Global Health, Umeå University, Umeå, Sweden
5. Division of Epidemiology and BiostatisticsSchool of Public Health, University of the Witwatersrand, Johannesburg, South Africa
6. Julius Global Health Julius Centre for Health Sciences and Primary Care, University Medical Centre Utrecht, Utrecht, The Netherlands