title: Comorbid behavioural problems in Tourette's syndrome are positively correlated with the severity of tic symptoms.
abstract: OBJECTIVE
  We studied the comorbid behavioural and mood problems in children with non-psychiatric Tourette's syndrome (TS) and their relationship with severity of tic disorder.
  
  
  METHODS
  Sixty-nine TS children and 69 healthy controls were assessed by Child Behavior Checklist (CBCL) and Yale Global Tic Severity Scale (YGTSS). The relationships between behavioural problems and severity of tic symptoms were analysed statistically by comparison, correlation and multiple linear regression.
  
  
  RESULTS
  Tourette's syndrome patients scored significantly lower (p<0.01) on the CBCL competency subscales and total score, and higher on all behavioural problem subscales and total score (p<0.01). Expectedly, the TS children had lower social competence than normal children. Among the TS children, the severity of tic symptoms is positively correlated with the severity of overall impairment in school and social competence. When the behavioural and mood problems commonly associated with TS were studied in detail, we found that delinquent behaviour, thought problems, attention problems, aggressive behaviour and externalizing are positively correlated with severity of tic symptoms.
  
  
  CONCLUSIONS
  The findings indicated that children with TS-only also had a broad range of behavioural problems, and some of these were related to the severity of tic symptoms.
authors.affiliation: Mental Health Centre, The Second Affiliated Hospital (Yu Quan Hospital) of the Medical School, Tsinghua University, Beijing, China. zhuyan4895025@hotmail.com
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Kai Man
authors.initials: KM
authors.lastname: Leung
authors.forename: Po-zi
authors.initials: PZ
authors.lastname: Liu
authors.forename: Ming
authors.initials: M
authors.lastname: Zhou
authors.forename: Lin-yan
authors.initials: LY
authors.lastname: Su
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000453:epidemiology*; D002648:Child; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis / Q000453:epidemiology*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D020323:Tics / Q000175:diagnosis* / Q000453:epidemiology*; D005879:Tourette Syndrome / Q000175:diagnosis / Q000453:epidemiology*