[1] Univ Pittsburgh, Grad Sch Publ Hlth, Dept Hlth Policy & Management, Pittsburgh, PA USA
[2] Sexual Hlth Innovat, New York, NY USA
[3] Johns Hopkins Bloomberg Sch Publ Hlth, Dept Biostat, Baltimore, MD USA
[4] Calif State Univ Sacramento, Davis Sch Med, Dept Internal Med, Sacramento, CA 95819 USA
[5] Eunice Kennedy Shriver Natl Inst Child Hlth & Hum, Epidemiol Branch, Div Intramural Populat Hlth Res, Bethesda, MD USA
[6] Johns Hopkins Univ, Sch Med, Dept Med, Div Gen Internal Med, Baltimore, MD 21205 USA
[7] Johns Hopkins Bloomberg Sch Publ Hlth, Dept Populat Family & Reprod Hlth, Baltimore, MD USA