Clinical validation of the parent-report Toronto Obsessive-Compulsive Scale (TOCS): A pediatric open-source rating...

Area of Science:

• Psychiatry and Psychology
• Neurodevelopmental Disorders
• Child and Adolescent Mental Health

Background:

• Existing obsessive-compulsive disorder (OCD) measures lack multipurpose utility for cross-disorder research and clinical assessment.
• A need exists for a reliable, quantitative OCD rating scale applicable across diverse patient populations.
• The Toronto Obsessive-Compulsive Scale (TOCS) was developed as a parent-report measure for obsessive-compulsive traits.

Purpose of the Study:

• To evaluate the psychometric properties of the parent-report Toronto Obsessive-Compulsive Scale (TOCS).
• To establish clinical cutoffs for the TOCS using receiver operating characteristic (ROC) analyses.
• To assess the TOCS's ability to discriminate between obsessive-compulsive disorder (OCD), attention-deficit/hyperactivity disorder (ADHD), and autism spectrum disorder (ASD).

Main Methods:

• Psychometric properties (confirmatory factor analysis, reliability, validity) of the TOCS were examined in a sample of 350 children and adolescents with OCD.
• Receiver operating characteristic (ROC) analyses were employed to establish TOCS clinical cutoffs using discovery and validation samples.
• Classification accuracy and TOCS scores were compared across OCD, ADHD (n=820), and ASD (n=794) groups, alongside typically developing controls (n=391).

Main Results:

• The TOCS demonstrated excellent diagnostic discrimination for OCD from controls (AUC ≥0.95, sensitivity 77%-92%, specificity 92%-98%).
• Established TOCS cutoffs achieved 85%-90% classification accuracy in an independent validation sample.
• The TOCS effectively discriminated OCD from ADHD (AUC ≥0.86) and ASD (AUC ≥0.81), with higher scores in the OCD group across most dimensions.

Conclusions:

• The parent-report TOCS is a reliable and valid measure for assessing obsessive-compulsive traits in youth.
• The TOCS exhibits strong sensitivity and specificity in differentiating OCD from controls, ADHD, and ASD.
• The TOCS is a valuable quantitative tool for clinical assessment, cross-disorder research, and population-based studies in pediatric mental health.