1. Department of Epidemiology, University of North Carolina Gillings School of Global Public Health, Chapel Hill, NC, USA
2. National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA, USA
3. Emory University School of Medicine, Atlanta, GA, USA
4. Emory Autism Center, Atlanta, GA, USA
5. Division of Child Psychiatry, Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, USA
6. Department of Population Health Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
7. Department of Epidemiology, University of Colorado School of Medicine, Aurora, CO, USA
8. Department of Community and Family Health, College of Public Health, University of South Florida, Tampa, FL, USA
9. Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA