1. Center for Human Nutrition; Department of International Health Johns Hopkins Bloomberg School of Public Health; Baltimore Maryland USA
2. Social & Behavioral Interventions Program, Department of International Health; Johns Hopkins Bloomberg School of Public Health; Baltimore Maryland USA
3. Asociación para la Prevención y Estudio del VIH/SIDA; Retalhuleu Guatemala
4. Nutrition Sciences Program & Department of Health Services; University of Washington School of Public Health; Seattle Washington USA