title: Obsessive-compulsive symptom dimensions in a population-based, cross-sectional sample of school-aged children.
abstract: BACKGROUND
  Obsessive-compulsive disorder can be expressed as four potentially overlapping obsessive-compulsive symptom (OCS) dimensions (OCSD) ("symmetry/ordering", "contamination/cleaning", "aggressive/sexual/religious" and "collecting/hoarding"). In clinical samples, some dimensions are more familial and associated with increased psychiatric comorbidity and malfunctioning. However, data concerning OCS and OCSD are scarce in non-clinical samples, particularly among children. The present study aims to estimate: (1) the prevalence and sex/age distribution of OCS/OCSD in a community-based sample of schoolchildren; (2) the association between OCS and additional clinical factors; and (3) the degree of familial aggregation of OCS/OCSD.
  
  
  METHODS
  OCS and OCSD were evaluated in 9937 Brazilian school-children (6-12 years-old) and their biological relatives using the Family History Screen. Data analyses included gradient estimated equations and post-hoc tests.
  
  
  RESULTS
  We included data on 9937 index-children, 3305 siblings (13-18 years-old), and 16,218 parents. Biological mothers were the informants in 87.6% of the interviews. OCS were present in 14.7% of the index-children; 15.6% of their siblings; 34.6% of their mothers and 12.1% of their fathers. The prevalence of OCS and each of the OCSD gradually increased from ages 6 to 12 years. Overall, OCS in children were associated with the presence of other psychiatric symptoms, as well as behavioral/school impairment. OCS and each of the four OCSD aggregated significantly within families.
  
  
  CONCLUSIONS
  OCS are prevalent and associated with psychiatric symptoms and clinical impairment among school-aged children. OCSD aggregate within families in a dimension-specific fashion. These findings suggest a natural continuum between OCS and OCD with regard to their dimensional character.
authors.affiliation: Department & Institute of Psychiatry, University of Sao Paulo Medical School (USP), Rua Dr. Ovídio Pires de Campos, 785, São Paulo 01060-970, SP, Brazil; National Institute of Developmental Psychiatry for Children and Adolescents, CNPq, Rua. Dr. Ovídio Pires de Campos, São Paulo 01060-970, SP, Brazil. Electronic address: pedrodealvarenga@gmail.com.
authors.forename: Pedro G
authors.initials: PG
authors.lastname: Alvarenga
authors.affiliation: Department & Institute of Psychiatry, University of Sao Paulo Medical School (USP), Rua Dr. Ovídio Pires de Campos, 785, São Paulo 01060-970, SP, Brazil.
authors.forename: Raony C
authors.initials: RC
authors.lastname: Cesar
authors.affiliation: Department & Institute of Psychiatry, University of Sao Paulo Medical School (USP), Rua Dr. Ovídio Pires de Campos, 785, São Paulo 01060-970, SP, Brazil; Child Study Center, Yale School of Medicine, 230, South Frontage Rd, New Haven, CT 06519, USA.
authors.forename: James F
authors.initials: JF
authors.lastname: Leckman
authors.affiliation: Department & Institute of Psychiatry, University of Sao Paulo Medical School (USP), Rua Dr. Ovídio Pires de Campos, 785, São Paulo 01060-970, SP, Brazil; National Institute of Developmental Psychiatry for Children and Adolescents, CNPq, Rua. Dr. Ovídio Pires de Campos, São Paulo 01060-970, SP, Brazil.
authors.forename: Tais S
authors.initials: TS
authors.lastname: Moriyama
authors.affiliation: Department of Neurology, Psychology and Psychiatry, Botucatu Medical School, São Paulo State University (UNESP), Av. Prof. Montenegro s/n, Botucatu 18618970, SP, Brazil. Electronic address: albinatorres@gmail.com.
authors.forename: Albina R
authors.initials: AR
authors.lastname: Torres
authors.affiliation: Child Study Center, Yale School of Medicine, 230, South Frontage Rd, New Haven, CT 06519, USA.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Bloch
authors.affiliation: Department of Neurology, Psychology and Psychiatry, Botucatu Medical School, São Paulo State University (UNESP), Av. Prof. Montenegro s/n, Botucatu 18618970, SP, Brazil. Electronic address: catherine.coughlin@yale.edu.
authors.forename: Catherine G
authors.initials: CG
authors.lastname: Coughlin
authors.affiliation: Department & Institute of Psychiatry, University of Sao Paulo Medical School (USP), Rua Dr. Ovídio Pires de Campos, 785, São Paulo 01060-970, SP, Brazil; National Institute of Developmental Psychiatry for Children and Adolescents, CNPq, Rua. Dr. Ovídio Pires de Campos, São Paulo 01060-970, SP, Brazil.
authors.forename: Marcelo Q
authors.initials: MQ
authors.lastname: Hoexter
authors.affiliation: National Institute of Developmental Psychiatry for Children and Adolescents, CNPq, Rua. Dr. Ovídio Pires de Campos, São Paulo 01060-970, SP, Brazil; Hospital de Clinicas de Porto Alegre, Federal University of Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2350, Porto Alegre 90035-903, RS, Brazil. Electronic address: gmanfro@gmail.com.
authors.forename: Gisele G
authors.initials: GG
authors.lastname: Manfro
authors.affiliation: Department & Institute of Psychiatry, University of Sao Paulo Medical School (USP), Rua Dr. Ovídio Pires de Campos, 785, São Paulo 01060-970, SP, Brazil; National Institute of Developmental Psychiatry for Children and Adolescents, CNPq, Rua. Dr. Ovídio Pires de Campos, São Paulo 01060-970, SP, Brazil. Electronic address: gvp.ez@terra.com.br.
authors.forename: Guilherme V
authors.initials: GV
authors.lastname: Polanczyk
authors.affiliation: Department & Institute of Psychiatry, University of Sao Paulo Medical School (USP), Rua Dr. Ovídio Pires de Campos, 785, São Paulo 01060-970, SP, Brazil; National Institute of Developmental Psychiatry for Children and Adolescents, CNPq, Rua. Dr. Ovídio Pires de Campos, São Paulo 01060-970, SP, Brazil.
authors.forename: Euripedes C
authors.initials: EC
authors.lastname: Miguel
authors.affiliation: National Institute of Developmental Psychiatry for Children and Adolescents, CNPq, Rua. Dr. Ovídio Pires de Campos, São Paulo 01060-970, SP, Brazil; Child and Adolescent Psychiatry Unit (UPIA), Department of Psychiatry, Federal University of São Paulo (UNIFESP), Rua Pedro de Toledo, 590, São Paulo 04038-020, SP, Brazil. Electronic address: mariaceica.rosario@gmail.com.
authors.forename: Maria C
authors.initials: MC
authors.lastname: do Rosario
mesh_terms: D000367:Age Factors; D002648:Child; D018672:Community Health Planning; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000453:epidemiology*; D011569:Psychiatric Status Rating Scales; D012111:Residence Characteristics; D012737:Sex Factors
keywords: Epidemiology; Family history; Obsessive-compulsive disorder; School children