1. Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota
2. Graduate Studies Program in Epidemiology, School of Medicine, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
3. Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina
4. Department of Biostatistics, University of North Carolina, Chapel Hill, North Carolina
5. Departments of Medicine and Epidemiology, Johns Hopkins University, Baltimore, Maryland
6. Department of Medicine, Baylor College of Medicine, Houston, Texas