Social FacilitationSocial BehaviorSocial ConformitySocial ValuesSocial EnvironmentSocial PerceptionSocial SupportSocial Control, InformalPeer GroupSocial ProblemsUniversitiesStudentsIntentionSocial IsolationAttitudeSocial IdentificationPunishmentGames, ExperimentalSocial ClassCultureSocial AdjustmentPhiladelphiaSocial DominanceAlcohol DrinkingHealth Knowledge, Attitudes, PracticeSocial MediaSocial WorkSocial StigmaHierarchy, SocialQuestionnairesRisk-TakingInterpersonal RelationsSocial SciencesFeedback, PsychologicalHealth PromotionMarketingAltruismDrug UsersSocial ChangeNeedle SharingSocial DistanceHealth BehaviorSocioeconomic FactorsSelf EfficacyAttitude to HealthSex FactorsHealth EducationCross-Sectional StudiesData CollectionAlcoholic IntoxicationModels, PsychologicalAdolescent BehaviorInterviews as TopicSocial ConditionsCross-Cultural ComparisonWomenSocial DesirabilityEmotionsSocial Behavior DisordersResidence CharacteristicsSelf ConceptFocus GroupsSocial SecuritySelf ReportQualitative ResearchUnited StatesPsychology, SocialSexual BehaviorSmokingSocial ParticipationHIV InfectionsSexual PartnersSocial WelfareSocial JusticeHealth SurveysUrban PopulationMotivationAge FactorsPhobic DisordersCaliforniaSpouse AbuseDecision MakingSocial MarketingSubstance-Related DisordersSocial AlienationSubstance Abuse, IntravenousInternetHomosexuality, MaleCondomsSocial MedicineProgram EvaluationLogistic ModelsNetherlandsStress, PsychologicalFriends