Initial Psychometric Properties of a Brief Parent-Report Instrument for Assessing Tic Severity in Children with Chronic Tic Disorders

Abstract

This article describes the development and initial psychometric properties of the Parent Tic Questionnaire (PTQ)—a new measure assessing the number, frequency, and intensity of motor and vocal tics in children and adolescents with Chronic Tic Disorder (CTD). Parents of 40 children with a CTD completed the PTQ as part of a larger assessment battery. Results show the PTQ to have excellent internal consistency and good to excellent 2-week test-retest reliability. The motor tic severity subscale, vocal tic severity subscale, and total severity score of the PTQ correlated highly with the corresponding scales of the gold-standard clinician-rated Yale Global Tic Severity Scale (YGTSS), indicating excellent convergent validity. Correlations between the YGTSS and PTQ remained strong after controlling for measures of obsessive-compulsive disorder and inattention, suggesting good discriminant validity. The PTQ is a promising supplement to current methods for assessing tic severity and further research on the validity, reliability, and clinical utility of the scale are warranted.

KEYWORDS:

• children and adolescents
• instrument development
• psychometrics
• tic disorders

This work was supported by collaborative research grants from the Tourette Syndrome Association to Douglas Woods, PhD (UWM) and John Piacentini, PhD (UCLA). The authors would also like to acknowledge the contributions of Liviu Bunaciu, Jordan Bonow, Ryan Walsh, Brecken Gilbert, Brian Buzzella, Araceli Gonzalez, Amanda Pearlman, and the children and their families who participated in this research.