Rates of OCD and ADHD were elevated in all four TS/CT disease definitions relative to controls (Table 3). OCD was present in 22% of TS Narrow and 20% of TS Intermediate subjects compared with 2% of controls (p < .001 for both groups), whereas 9% of CT Narrow and 10% of CT Intermediate subjects had OCD (p = .039 and p < .001, respectively). The frequency of ADHD was 17% in TS Narrow and 18% in TS Intermediate, 14% in CT Narrow and 11% in CT Intermediate, compared with 2% in controls (p < .001 for all comparisons). There was no evidence of heterogeneity between the Narrow and Intermediate definitions for either TS or CT with respect to OCD or ADHD (I2 = 0% to 2.5%). Rates of OCD and ADHD were also elevated compared with controls in the CMT Narrow/Intermediate and CVT Narrow/Intermediate groups, with a slightly higher rate of OCD in CVT Narrow and Intermediate (17% and 12%, respectively) relative to CMT Narrow (4%) and CMT Intermediate (9%) (Table S3, available online). Rates of co-occurring ADHD were 13%
