enquête (2) âge (2) Youth (2) Young adults (2) Swiss (2) Sex (2) Females (2) Age (2) Age (2) jeunesse (1) temps (durée) (1) comportement (1) établissement scolaire (1) ressources (1) recherche (1) pression (1) association (1) papier (1) effet (1) éducation (1) internet (1) sujet (1) Education (1) Internet (1) Rates (1) Sexually transmitted diseases (1) Time (1) Social groups (1) Sex instruction (1) Respect (1)