1. Department of Biostatistics, Johns Hopkins University, Baltimore, MD;
2. Division of Biostatistics and Bioinformatics, University of California, San Diego, La Jolla, CA;
3. Department of Epidemiology, Johns Hopkins University, Baltimore, MD;
4. Enda-Sante, Dakar, Senegal;
5. Ministry of Health, Cote d’Ivoire, Abidjan, Ivory Coast;
6. Department of Epidemiology, University of North Carolina, Chapel Hill, Chapel Hill, NC;
7. Department of Statistics, Penn State University, State College, PA