A Study of Cranial Electrotherapy Stimulation as an Add-on Treatment for Tic Disorders (SCATT)

The investigators will conduct a randomized, double‐blind, sham‐controlled trial to determine the efficacy of CES as an add‐on treatment for tic disorders (SCATT). The study will be conducted at an outpatient, single‐center academic setting. A total of 100 patients aged 6 to 17 years with tic disorders and lack of clinical response to 4 weeks' pharmacotherapy will be enrolled. Patients will be randomly into 2 groups and given 4 weeks' treatment, including 40 daily 30‐minute sessions of active CES(500μA 2mA) or sham CES(lower than 100μA) on weekdays. Change in Yale Global Tic Severity Scale (YGTSS) is considered to be the primary outcome. The secondary outcome is the changes in Clinical Global Impression (CGI) and Hamilton Anxiety Scale (HAMA). Assessments will be performed at baseline, week 2, week 4 and week 8. Adverse events(AE) will be also evaluated.