Objective: To study prevalence and comorbidity of Tourette's disorder in th
e general population of children and in a clinical setting. Method: School-
age children in the general population and children attending a county-wide
tic disorder clinic were screened and examined by the same doctor. Behavio
ral-psychometric instruments with demonstrated reliability and validity wer
e used. Results: Depending on the sample characteristics, 0.15% to 1.1% of
all children had Tourette's disorder. Boys outnumbered girls by 4:1 through
6:1.Attention deficits and empathy/autism spectrum problems (including Asp
erger's disorder) were Very common, each type of comorbidity affecting appr
oximately two thirds of individuals with Tourette's disorder. Overall behav
ior problem scores were high, and affected children exhibited a marked degr
ee of functional impairment. Conclusions: Tourette's disorder is a common d
isorder with high rates of significant comorbidity. in most cases, attentio
n deficits and empathy problems are likely to cause more suffering than the
tics per se.