1. Heidelberg Institute of Global Health, University of Heidelberg, Im Neuenheimer Feld 672, 69120Heidelberg, Germany.
2. School of Health and Social Development, Deakin University, Victoria, Australia.
3. Institute for Medical Informatics, Biometry & Epidemiology, Ludwig-Maximilians University, Munich, Germany.
4. Faculty of Medical and Health Sciences, University of Auckland, New Zealand.
5. Health Section, United Nations Children's Fund, New York, United States of America.
6. Centre for Global Health, Department of Public Health, Aarhus University, Denmark.