1. Department of Epidemiology and Medical Statistics, Faculty of Public Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
2. Division of Health Promotion and Behavioral Science, School of Public Health, San Diego State University, San Diego, CA, USA
3. Center on Gender Equity and Health, University of California San Diego, Division of Infectious Disease and Global Public Health, La Jolla, CA, USA
4. Division of Epidemiology and Biostatistics, School of Public Health, San Diego State University, San Diego, CA, USA