Background. Previous research has reported co-morbidity between attention deficit hyperactivity disorder (ADHD) and anxiety disorders. Interpretation of these findings is complicated by symptom overlap in the clinical presentation of the disorders. We estimate the prevalence of ADHD in both the current and childhood histories of adults with anxiety disorders, while taking symptom overlap into account. We also evaluate the utility of the Wender Utah Rating Scale (WURS) for retrospective reporting of ADHD.

Methods. Consecutive admissions (N=149) to an anxiety disorders clinic were given a diagnostic and psychometric assessment. The WURS was administered to obtain a retrospective diagnosis of childhood ADHD. Twenty-nine of the 35 people surpassing the cut-off score on the WURS were given a structured interview of adult ADHD symptoms.

Results. The WURS contains many ‘internalizing’ items that may inflate retrospective accounts of ADHD. After taking this into account, there is still a significantly higher prevalence of ADHD in the retrospective reports of adults with anxiety disorders (15%) than would be expected by chance (4%). Furthermore, of those who meet retrospective criteria for ADHD, 45% (13 of 29) continue to meet diagnostic criteria for ADHD as adults.

Conclusions. The WURS may require considerable revision for use with clinical populations. In spite of these difficulties with retrospective assessment, available evidence indicates that ADHD is more prevalent in the histories of anxiety disordered patients than would be expected from base rates.