Autistic DisorderIncidenceAsperger SyndromeRegression (Psychology)Social BehaviorRisk FactorsLanguage Development DisordersStereotyped BehaviorDevelopmental DisabilitiesRetrospective StudiesCommunication DisordersStereotypic Movement DisorderCohort StudiesProspective StudiesIntellectual DisabilityPlay and PlaythingsNonverbal CommunicationTime FactorsCase-Control StudiesFollow-Up StudiesInfant, NewbornRegistriesAge DistributionSiblingsTreatment OutcomeFragile X SyndromePrevalenceVerbal BehaviorBrainGenetic Predisposition to DiseaseUnited StatesMagnetic Resonance ImagingIntelligenceSex DistributionSocial PerceptionPregnancyPopulation SurveillanceImitative BehaviorEducation, SpecialParentsNeuropsychological TestsRiskSeverity of Illness IndexLanguage DisordersPhenotypeInterpersonal RelationsRisk AssessmentSocial Behavior DisordersIntelligence TestsEarly Intervention (Education)NeoplasmsPostoperative ComplicationsAttentionDNA Copy Number VariationsLanguage TherapyMacrocephalyPaternal AgeBehavior TherapyChild DevelopmentLanguageCaliforniaLongitudinal StudiesAnalysis of VarianceGeneralization (Psychology)Chromosomes, Human, Pair 15SwedenRett SyndromeEndophenotypesGroomingJapanPoisson DistributionLanguage DevelopmentMainstreaming (Education)ComorbidityCommunicationTheory of MindSeasonsFacial ExpressionChild BehaviorLanguage TestsFaceBrain MappingCompulsive BehaviorQuestionnairesPersonal Construct TheorySymbolismMethyl-CpG-Binding Protein 2Fragile X Mental Retardation ProteinGenotypeDenmarkCognitionDisease Models, AnimalSurvival RatePerceptual DisordersNeural PathwaysChromosome DuplicationLogistic ModelsImage Processing, Computer-AssistedPrognosisChild Language