Prevalence of tics in schoolchildren and association with placement in special education

Background: Based on the knowledge that Tourette's syndrome (TS) is associated with several clinical features that can impair school function and growing evidence that the disorder is much more common than previously thought, the authors hypothesized that TS and related tic disorders would be associated with school problems in the childhood population at large. Methods: Direct, blinded (to educational placement) interviews of 1,596 schoolchildren in Monroe County, Rochester, NY, were conducted. Results: Twenty-seven percent of 341 students classified as receiving special education (SpEd) had tics compared with 19.7% (p = 0.008) of 1,255 students in regular classroom programs (RegEd). The weighted prevalence estimates for tics were 23.4% in SpEd and 18.5% in RegEd. A higher percentage of students in SpEd (7.0%) met diagnostic criteria for TS than students in RegEd (3.8%; p = 0.01). Conclusions: Although possibly influenced by selection bias, our results indicate that tic disorders are common in children and are highly associated with school dysfunction. Tics may represent an identifiable sign of an underlying brain developmental disorder that contributes to academic difficulties.