title: Prevalence of psychiatric disorders in a Brazilian birth cohort of 11-year-olds.
abstract: OBJECTIVE
  To estimate the prevalence of psychiatric disorders in preadolescents aged 11-12 years from a birth cohort in a southern Brazilian city.
  
  
  METHODS
  This is a cross-sectional investigation nested in a cohort study with a two-phase design: screening and diagnosis. In the screening phase, 4,452 preadolescents and their mothers were interviewed with the Strengths and Difficulties Questionnaire (SDQ). In the diagnostic phase, all preadolescents with a positive SDQ (n = 122) and their mothers answered the Development and Well-Being Assessment for Children and Adolescents (DAWBA). A sample randomly selected among the cohort participants with a negative SDQ served as a control group (158 subjects and their mothers) and was also assessed using the DAWBA.
  
  
  RESULTS
  After adjustment for the performance of the screening instrument, 10.8% (95% CI 7.1-14.5) of the preadolescents showed at least one psychiatric disorder according to either the DSM-IV or the ICD-10. The most prevalent disorders were disruptive behavior (prevalence rates were 8.5% according to the DSM-IV and 7.1% according to the ICD-10) and anxiety disorders (prevalence rates were 6.0% according to the DSM-IV and 6.2% according to the ICD-10).
  
  
  CONCLUSIONS
  Both overall and individual prevalence rates of psychiatric disorders found in this study are in the same range of other international studies, although slightly higher than findings from developed countries. The results corroborate previous findings from other epidemiological studies in children and adolescents suggesting the universality of psychiatric disorders across cultures.
authors.affiliation: Post-Graduate Program in Psychiatry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil. luanselmi@terra.com.br
authors.forename: Luciana
authors.initials: L
authors.lastname: Anselmi
authors.forename: Bacy
authors.initials: B
authors.lastname: Fleitlich-Bilyk
authors.forename: Ana Maria B
authors.initials: AM
authors.lastname: Menezes
authors.forename: Cora L
authors.initials: CL
authors.lastname: Araújo
authors.forename: Luis A
authors.initials: LA
authors.lastname: Rohde
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001008:Anxiety Disorders / Q000175:diagnosis / Q000453:epidemiology; D019958:Attention Deficit and Disruptive Behavior Disorders / Q000175:diagnosis / Q000453:epidemiology; D001938:Brazil / Q000453:epidemiology; D002648:Child; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D019049:Developed Countries / Q000706:statistics & numerical data; D039721:Diagnostic and Statistical Manual of Mental Disorders; D006801:Humans; D038801:International Classification of Diseases; D001523:Mental Disorders / Q000175:diagnosis / Q000453:epidemiology*; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D011795:Surveys and Questionnaires; D014505:Urban Population / Q000706:statistics & numerical data