Obsessive-compulsive scale of the child behavior checklist: Specificity, sensitivity, and predictive power

Objective. To create an obsessive-compulsive disorder subscale (OCS) of the Child Behavior Checklist (CBCL) and to determine its internal consistency, sensitivity, specificity, and positive and negative predictive power to id entify obsessive-compulsive disorder (OCD) in children and adolescents. Methods. Three samples of equal size (n = 73) of children and adolescents, matched for age, gender, and race, were selected for these analyses: 1) a c linically ascertained OCD group, 2) a psychiatrically treated group whose r ecords revealed no evidence of OCD, and 3) a general population control gro up. An OCS was created by applying factor analysis to 11 CBCL items. Examin ations of internal consistency, sensitivity, specificity, and positive and negative predictive value were undertaken. Results. Of 11 items hypothesized to predict OCD, 8 items were retained aft er factor analyses (smallest factor loading: 0.49) and used to calculate OC S scores. The retained items displayed excellent internal consistency (Cron bach's alpha coefficient = 0.84). OCD participants had significantly higher OCS scores than either psychiatrically treated or general population contr ol groups. With the use of the 2 cutoff scores closest to the true rate of OCD in the overall sample, sensitivity was 75.3% to 84.9%, specificity was 82.2% to 92.5%, positive predictive value was 70.5% to 83.3%, and negative predictive value was 88.2% to 91.6%. Conclusion. The performance of the proposed CBCL OCS compares favorably wit h that of the only previously studied screening instrument for OCD, the Ley ton Obsessional Inventory-Child Version. Unlike the Leyton Obsessional Inve ntory-Child Version, the CBCL is already in widespread use as a screen for most other forms of psychopathology. As the performance of the CBCL OCS wil l need to be replicated in other sample populations, data with various cuto ff levels are provided to enable investigators and clinicians to tailor its use to specific study populations.