1. Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
2. Department of Developmental Neurobiology, Instituto Nacional de Perinatologia, Mexico City, Mexico
3. Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut, USA
4. Channing Laboratory, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
5. Division of Statistics, Center for Evaluation Research and Surveys, National Institute of Public Health, Cuernavaca, Morelos, Mexico
6. Ministry of Health, Mexico City, Mexico
7. Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
8. Department of Neurology, Harvard Medical School and Children’s Hospital Boston, Boston, Massachusetts, USA
9. Department of Emergency Medicine, Children’s Hospital Boston, Boston, Massachusetts, USA