Quantitative and qualitative aspects of obsessive-compulsive behaviour in children with attention-deficit hyperactivity disorder compared with tic disorder

Objective: Within the framework of associated psychopathology in child psyc hiatric disorders, this study focused on quantitative and qualitative aspec ts of obsessive-compulsive behaviour (OCB) in both attention-deficit hypera ctivity disorder (ADHD) and chronic tic disorder/Tourette's disorder (TD). Method: Forty-two healthy controls, 41 children with ADHD and 38 children w ith TD, aged 9-13 years, were investigated using the Leyton Obsessional Inv entory - Child Version (LOI-CV), the Child Behaviour Checklist (CBCL) and a n expert-rated structured parent interview to reflect a cross-informant vie w of OCB. Results: Unexpectedly, self-reports of children with ADHD rather than child ren with TD showed the highest OCB scores in the LOT-CV. Qualitatively, ADH D-related OCB focused on the item subsets concerning 'dirt and contaminatio n', 'repetition', 'overconscientiousness', and 'hoarding'. In the parent-ra ted CBCL, similar levels of OCB were reported for ADHD and TD patients. In contrast, only children with TD showed clinically relevant OCB according to expert ratings. Conclusion: Not only young TD patients but also children with ADHD should b e investigated and monitored carefully for quantitative and qualitative asp ects of OCB comorbidity.