1. National Institute of Public Health, Cuernava; Morelos Mexico
2. Department of Chronic Disease Epidemiology; Yale School of Public Health; New Haven CT USA
3. Department of Nutritional Sciences; University of Michigan School of Public Health; Ann Arbor MI USA
4. Dalla Lana School of Public Health; University of Toronto; Toronto ON Canada
5. Department of Nutrition and Department of Social and Behaviorial Sciences; Harvard School of Public Health; Boston MA USA