Systematic review of severity scales and screening instruments for tics: Critique and recommendations

Several clinician, informant, and self-report instruments for tics and associated phenomena have been developed that differ in construct, comprehensiveness, and ease of administration.

A Movement Disorders Society subcommittee aimed to rate psychometric quality of severity and screening instruments for tics and related sensory phenomena.

Following the methodology adopted by previous Movement Disorders Society subcommittee papers, a review of severity and screening instruments for tics was completed, applying a classification as "recommended," "suggested," or "listed" to each instrument.

A total of 5 severity scales (Yale Global Tic Severity Scale, Tourette Syndrome Clinical Global Impression, Tourette's Disorder Scale, Shapiro Tourette syndrome Severity Scale, Premonitory Urges for Tics Scale) were "recommended," and 6 (Rush Video-Based Tic Rating Scale, Motor tic, Obsessions and compulsions, Vocal tic Evaluation Survey, Tourette Syndrome Global Scale, Global Tic Rating Scale, Parent Tic Questionnaire, Tourette Syndrome Symptom List) were "suggested." A total of 2 screening instruments (Motor tic, Obsession and compulsions, Vocal tic Evaluation Survey and Autism-Tics, Attention Deficit/Hyperactivity Disorder and Other Comorbidities Inventory) were "recommended," whereas 2 others (Apter 4-questions screening and Proxy Report Questionnaire for Parents and Teachers) were "suggested."

Our review does not support the need for developing new tic severity or screening instruments. Potential objectives of future research include developing a rating instrument targeting the full spectrum of tic-related abnormal behaviors, assessing/screening malignant forms of tic disorders, and developing patient-reported outcome measures. © 2017 International Parkinson and Movement Disorder Society.