[1] Univ N Carolina, Clin Res Program, Wilmington, NC 28401 USA
[2] INC Res, Post Approval & Strateg Serv, Wilmington, NC USA
[3] Degge Grp, Alexandria, VA USA
[4] Univ Rochester, Med Ctr, Rochester, NY 14642 USA
[5] Indiana Univ, Sch Med, Indianapolis, IN USA
[6] Harvard Univ, Sch Med, Boston, MA USA
[7] Ctr Dis Control & Prevent, Div Birth Defect & Dev Disabil, Atlanta, GA USA
[8] Univ Texas SW Med Ctr Dallas, Dallas, TX 75390 USA