[1] CDCP, Natl Ctr Birth Defects & Dev Disabil, 4770 Buford Hwy,Mailstop S106-3, Atlanta, GA 30341 USA
[2] Massachusetts Gen Hosp Children, Med Genet, Boston, MA USA
[3] Univ Arkansas Med Sci, Fay W Boozman Coll Publ Hlth, Dept Epidemiol, Little Rock, AR USA
[4] Univ Arkansas Med Sci, Arkansas Ctr Birth Defects Res & Prevent, Little Rock, AR USA
[5] Univ Arizona, Dept Pediat, Tucson, AZ USA
[6] Univ Arkansas Med Sci, Fay W Boozman Coll Publ Hlth, Dept Hlth Policy & Management, Little Rock, AR USA
[7] Childrens Healthcare Atlanta, Atlanta, GA USA
[8] Emory Univ, Sch Med, Atlanta, GA USA