Properties, Dimensions, and Heritability of Obsessive-Compulsive Symptoms in a Community Sample of Children and Adolescents

Obsessive-compulsive disorder (OCD) is a debilitating neuropsychiatric disorder commonly seen in children and adolescents. The etiology of OCD remains elusive mostly due to its complex, heterogeneous phenotype and genotype. Increasing evidence support a multidimensional model of OCD and a continuous nature of obsessive-compulsive (OC) symptoms in the general population. However, there is limited understanding of OC symptoms in pediatric populations. Using a novel questionnaire, the Toronto Obsessive Compulsive Scale, we investigated properties, dimensions, and heritability of OC symptoms in a community sample of 16,380 children and adolescents, and a sub-sample of 220 twin pairs, respectively. We identified six distinct OC symptom dimensions in our study that parallel those identified in previous studies: (1) Superstition, (2) Cleaning/Contamination, (3) Hoarding, (4) Symmetry/Ordering, (5) Checking/Counting, (6) Rumination. Phenotypic and heritability characteristics of overall and dimensions of OC symptoms are reviewed in detail. Research and clinical implications of the current study are also discussed.MAS