1. Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
2. University of Tennessee, Knoxville, TN, USA.
3. Ministry of Health, San José, Costa Rica.
4. School of Public Health, University of Costa Rica, San José, Costa Rica.
5. Center for Health Systems and Policy Research at GIMPA, Accra, Ghana.
6. London School of Hygiene and Tropical Medicine, London, UK.