1. aDepartment of International Health, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD, 21205, United States of America (USA).
2. bDepartment of Population, Family and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA.
3. cGAVI Alliance, Geneva, Switzerland.
4. dIndian Institute of Health Management Research, Rajasthan, India.
5. eDepartment of Monitoring and Evaluation, Ministry of Public Health, Kabul, Afghanistan.