1. National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA (K.F.D., C.E.R., M.E.O., S.L.F.).
2. Department of Epidemiology, Fay W. Boozman College of Public Health and the Arkansas Center for Birth Defects Research and Prevention, University of Arkansas for Medical Sciences, Little Rock (W.N.N.).
3. Department of Pediatrics, University of Arizona, Tucson (J.G.A., S.E.K.).
4. Department of Pediatrics, Center for Applied Research and Evaluation, College of Medicine, Little Rock, AR (A.G.).
5. Children’s Healthcare of Atlanta and Emory University School of Medicine, Atlanta, GA (M.E.O.).