[1] CDC, Emerging Invest & Analyt Methods Branch, Div Adult & Community Hlth, Natl Ctr Chron Dis Prevent & Hlth Promot, Atlanta, GA 30341 USA
[2] Carter Consulting Inc, Atlanta, GA USA
[3] WHO, Dept Injuries & Violence Prevent, CH-1211 Geneva, Switzerland
[4] Kaiser Permanente, Dept Prevent Med, San Diego, CA USA