1. Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA
2. Department of Global Health, University of Washington, Seattle, USA
3. PATH-Kenya, Kisumu, Kenya
4. Department of Biostatistics, University of Washington, Seattle, USA
5. Department of Medical Ethics and Health Policy, University of Pennsylvania, Philadelphia, USA
6. School of Nursing, University of Washington, Seattle, USA
7. Ministry of Health, Nairobi, Kenya
8. Kenya Medical Research Institute (KEMRI), Nairobi, Kenya
9. Department of Medicine, University of Washington, Seattle, USA