To the Editor.—
Pauls et al1 claim that Tourette's syndrome (TS) and attention deficit disorder with hyperactivity (ADDH) are unrelated entities based on a small study of 27 families in which the two appeared to segregate independently. They suggest that when ADDH is present in TS, it is simply due to ascertainment bias. We disagree with this view and give the following evidence that attention deficit disorder (ADD) with or without hyperactivity (ADD/H) is a common manifestation of TS.
1. Attention deficit disorder and ADDH are common in patients with TS.—
Virtually every investigator who has studied a significant number of patients with TS has reported the presence of ADDH in approximately half of the cases.2-8 This adds up to 1473 patients, including 250 cases that we reported earlier, plus an additional new series of 246 patients that was studied by an extensive structured interview based on the