1. David B. Dunson is Senior Investigator, Biostatistics Branch, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709 . Amy H. Herring is Associate Professor of Biostatistics, University of North Carolina, Chapel Hill, NC 27599. Stephanie M. Engel is Assistant Professor, Department of Community and Preventive Medicine, Mount Sinai Medical School, New York, NY 10029. This research was supported in part by the Intramural Research Program of the NIH, National Institute of...