1. Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts, USA
2. Department of Environmental Health Sciences, and
3. Department of Biostatistics, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
4. Division of Statistics, Center for Surveys and Evaluation Research, National Institute of Public Health, Cuernavaca, Morelos, México
5. Division of Research on Public Health, National Institute of Perinatology, Mexico City, México
6. Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
7. Channing Laboratory, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
8. Department of Chronic Disease Epidemiology, Yale School of Public Health, New Haven, Connecticut, USA
9. Ministry of Health, Distrito Federal, México