Lifetime diagnoses of DSM-IV-TR OCD and ADHD were derived using a self-report version of the Development and Well Being Assessment (DAWBA) parent interview that was completed by ALSPAC mothers about their children as part of the age 7, 10, and 14 questionnaires.25 The presence of recurrent obsessions or compulsions (response of “sometimes” or “often” to 1 or more of 7 questions about contamination, cleaning, checking, repeating, touching, arranging, or counting symptoms) that were severe enough either to last >1 hour a day, “waste a lot of time,” cause significant distress (“upset a great deal”), or cause interference or impairment (answers of “Quite a lot” or “A great deal” to five questions about interference with family, friends, school, or hobbies) at one of the three time points was required for a diagnosis of OCD. Recognition of these thoughts as excessive or unreasonable was not required per DSM-IV-TR guidelines for diagnosing OCD in children. Similarly, the presence of six of nine inattentive and/or six of nine hyperactive/impulsive symptoms, starting before age 7 years and causing interference in at least two of four settings (family, friends, school, leisure activities) were required to meet criteria for ADHD.
