| Institution: | 1. Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina;2. Department of Medicine, University of North Carolina, Chapel Hill, North Carolina;6. Department of Biostatistics, University of North Carolina, Chapel Hill, North Carolina;3. Department of Epidemiology, Johns Hopkins University, Baltimore, Maryland;4. Department of Medicine, Johns Hopkins University, Baltimore, Maryland;5. National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland |
