1. Division of Reproductive Health, Centers for Disease Control and Prevention, Atlanta, Georgia;
2. Oak Ridge Institute for Science and Education (ORISE) Research Participant Program, Division of Reproductive Health, Centers for Disease Control and Prevention, Atlanta, Georgia;
3. DB Consulting Group, Inc., Atlanta, Georgia;
4. Division of Vital Statistics, National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland;
5. Office of Chief Medical Examiner, State of New Hampshire, New Hampshire;
6. National Center for Child Death Review, Michigan Public Health Institute, Okemos, Michigan;
7. Departments of Family Medicine and Public Health Sciences, University of Virginia, Charlottesville, Virginia; and
8. Division of Pediatric Allergy, Immunology and Pulmonary Medicine, Washington University, St Louis, Missouri