1. Biostatistics, Department of Basic Clinical PracticeUniversity of Barcelona Barcelona Spain
2. Division of HIV/AIDS Prevention Surveillance and Epidemiology BranchNational Center for HIV/AIDSViral Hepatitis, STD, and TB PreventionCenters for Disease Control and PreventionAtlanta Georgia USA
3. Unitat de Suport de BarcelonaInstitut Universitari d'Investigacio en Atencio Primaria Jordi GolBarcelona Spain