1. Department of Population, Family, and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
2. Department of Community – Public Health, Johns Hopkins School of Nursing, Baltimore, MD, USA
3. Planned Parenthood of Maryland, Johns Hopkins Hospital, Baltimore, MD, USA
4. Division of Social and Behavioral Sciences, Yale School of Public Health and the Center for Interdisciplinary Research on AIDS, Yale University, New Haven, CT, USA