[1] Med Coll Wisconsin, Dept Emergency Med, Milwaukee, WI 53226 USA
[2] Univ S Carolina, Dept Epidemiol & Biostat, Arnold Sch Publ Hlth, Columbia, SC 29208 USA
[3] Med Coll Wisconsin, Injury Res Ctr, Milwaukee, WI 53226 USA
[4] Zhejiang Univ, Sch Publ Hlth, Injury Control Res Ctr, Hangzhou 310003, Zhejiang, Peoples R China
[5] Zhejiang Univ, Obes & Body Composit Res Ctr, Hangzhou 310003, Zhejiang, Peoples R China