1. Global Health and Tropical Medicine & WHO Collaborating Center on Health Workforce Policy and Planning, Institute of Hygiene and Tropical Medicine - NOVA University of Lisbon, Lisbon, Portugal.
2. School of Medicine, Duke University, Durham, NC, USA.
3. Duke Global Health Institute, Duke University, Durham, NC, USA.
4. Physical Medicine and Rehabilitation Service, Durham Veterans Administration Medical Center, Durham, NC, USA.
5. Division of Geriatrics, Department of Medicine, Duke University Medical Center, Durham, NC, USA.
6. Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore.