title: Principal components analysis of obsessive-compulsive disorder symptoms in children and adolescents.
abstract: BACKGROUND
  Obsessive-compulsive disorder (OCD) has a broadly diverse clinical expression that may reflect etiologic heterogeneity. Several adult studies have identified consistent symptom dimensions of OCD. The purpose of this study was to conduct an exploratory principal components analysis of obsessive-compulsive (OC) symptoms in children and adolescents with OCD to identify improved phenotypes for future studies.
  
  
  METHODS
  This study examined lifetime occurrence of OC symptoms included in the 13 symptom categories of the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS). Principal components analysis with promax rotation was performed on 231 children and adolescents with OCD and compared with results of similar adult studies.
  
  
  RESULTS
  A four-factor solution emerged explaining 59.8% of symptom variance characterized by 1) symmetry/ordering/repeating/checking; 2) contamination/cleaning/aggressive/somatic; 3) hoarding; and 4) sexual/religious symptoms. All factors included core symptoms that have been consistently observed in adult studies of OCD.
  
  
  CONCLUSIONS
  In children and adolescents, OCD is a multidimensional disorder. Symptom dimensions are predominantly congruent with those described in similar studies of adults with OCD, suggesting fairly consistent covariation of OCD symptoms through the developmental course. Future work is required to understand changes in specific symptom dimensions observed across the life span.
authors.affiliation: Psychiatric and Neurodevelopmental Genetics Unit, Massachusetts General Hospital, Department of Psychiatry, Harvard Medical School, Boston, Massachusetts 02114, USA.
authors.forename: S Evelyn
authors.initials: SE
authors.lastname: Stewart
authors.forename: Maria C
authors.initials: MC
authors.lastname: Rosario
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Brown
authors.forename: Alice S
authors.initials: AS
authors.lastname: Carter
authors.forename: James F
authors.initials: JF
authors.lastname: Leckman
authors.forename: Denis
authors.initials: D
authors.lastname: Sukhodolsky
authors.forename: Liliya
authors.initials: L
authors.lastname: Katsovitch
authors.forename: Robert
authors.initials: R
authors.lastname: King
authors.forename: Daniel
authors.initials: D
authors.lastname: Geller
authors.forename: David L
authors.initials: DL
authors.lastname: Pauls
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000374:Aggression / Q000523:psychology; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000453:epidemiology*; D010641:Phenotype; D025341:Principal Component Analysis; D011569:Psychiatric Status Rating Scales; D012737:Sex Factors; D012725:Sexual Behavior