1. aNational Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia
2. bUniversity of Utah, Salt Lake City, Utah
3. cUniversity of Texas at San Antonio, San Antonio, Texas
4. dUniversity of Arkansas for Medical Sciences, Little Rock, Arkansas
5. eUniversity of Wisconsin, Madison, Wisconsin
6. fJohns Hopkins Bloomberg School of Public Health, Baltimore, Maryland