[1] CDC, Hlth Studies Br, Natl Ctr Environm Hlth, Atlanta, GA 30333 USA
[2] Nationwide Childrens Hosp, Ctr Injury Res & Policy, Columbus, OH USA
[3] Ohio State Univ, Columbus, OH 43210 USA
[4] Nationwide Childrens Hosp, Ctr Injury Res & Policy, Columbus, OH USA
[5] CDC, EIS, Atlanta, GA 30333 USA