title: The Child and Adolescent Twin Study in Sweden (CATSS).
abstract: The Child and Adolescent Twin Study in Sweden (CATSS) is an ongoing longitudinal twin study targeting all twins born in Sweden since July 1, 1992. Since 2004, parents of twins are interviewed regarding the children's somatic and mental health and social environment in connection with their 9th or 12th birthdays (CATSS-9/12). By January 2010, 8,610 parental interviews concerning 17,220 twins had been completed, with an overall response rate of 80%. At age 15 (CATSS-15) and 18 (CATSS-18), twins and parents complete questionnaires that, in addition to assessments of somatic and mental health, include measures of personality development and psychosocial adaptation. Twin pairs in CATSS-9/12 with one or both twins screening positive for autism spectrum disorders, attention deficit/hyperactivity disorder, tic disorders, developmental coordination disorder, learning disorders, oppositional defiant disorder, conduct disorder, obsessive-compulsive disorder, and/or eating problems have been followed with in-depth questionnaires on family, social environment and personality, and subsequently by clinical assessments at age 15 together with randomly selected population controls, including 195 clinically assessed twin pairs from the first 2 year cohorts (CATSS-15/DOGSS). This article describes the cohorts and study groups, data collection, and measures used. Prevalences, distributions, heritability estimates, ages at onset, and sex differences of mental health problems in the CATSS-9/12, that were analyzed and found to be overall comparable to those of other clinical and epidemiological studies. The CATSS study has the potential of answering important questions on the etiology of childhood mental health problems and their role in the development of later adjustment problems.
authors.affiliation: Institute of Neuroscience and Physiology, Forensic Psychiatry, University of Gothenburg, Sweden. henrik.anckarsater@neuro.gu.se
authors.forename: Henrik
authors.initials: H
authors.lastname: Anckarsäter
authors.forename: Sebastian
authors.initials: S
authors.lastname: Lundström
authors.forename: Linnea
authors.initials: L
authors.lastname: Kollberg
authors.forename: Nora
authors.initials: N
authors.lastname: Kerekes
authors.forename: Camilla
authors.initials: C
authors.lastname: Palm
authors.forename: Eva
authors.initials: E
authors.lastname: Carlström
authors.forename: Niklas
authors.initials: N
authors.lastname: Långström
authors.forename: Patrik K E
authors.initials: PK
authors.lastname: Magnusson
authors.forename: Linda
authors.initials: L
authors.lastname: Halldner
authors.forename: Sven
authors.initials: S
authors.lastname: Bölte
authors.forename: Christopher
authors.initials: C
authors.lastname: Gillberg
authors.forename: Clara
authors.initials: C
authors.lastname: Gumpert
authors.forename: Maria
authors.initials: M
authors.lastname: Råstam
authors.forename: Paul
authors.initials: P
authors.lastname: Lichtenstein
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000453:epidemiology*; D001321:Autistic Disorder / Q000175:diagnosis / Q000453:epidemiology*; D002648:Child; D004200:Diseases in Twins / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007407:Interviews as Topic; D008137:Longitudinal Studies; D008297:Male; D058027:Neuropsychiatry; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis / Q000453:epidemiology*; D010290:Parents; D015995:Prevalence; D015203:Reproducibility of Results; D012737:Sex Factors; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology; D013981:Tic Disorders / Q000175:diagnosis / Q000453:epidemiology*