1. Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK
2. School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
3. Institute for Global Health, University College London, Gower Street, London WC1E 6BT, UK
4. Institute for Healthcare Improvement, Addis Ababa, Ethiopia
5. Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK