TABLE 3.

Clinical information of patients with tic disorder (TD) and healthy controls (HCs).^a

No.	Study	Diagnoses (n)	Diagnostic instrument	Disease duration (SD), year	YGTSS scores (SD)	Comorbidities (n)	GSI (SD)	Gastrointestinal disturbances (%)	Medication (n)
1	Lee and Wong (2018)	TS: severe tics (14); mild tics (10)	N/A	severe tics: 4.5 (2.33) mild tics: 2.25 (2.5)	TTS scores: severe tics, 27.4 (7.5); mild tics, 14.8 (4.1)	N/A	N/A	N/A	N/A
2	Zhao et al. (2020)	TS	DSM-5	1.5–4	YGTSS-TTS > 13	ADHD (3), variant asthma (1)	N/A	N/A	Tiapride (3); aripiprazole (2); trihexyphenidyl (2); risperidone (1)
3	Xi et al. (2021)	TD: TS (23); PTD (17); CTD (9)	DSM-5	2.11 (1.92)	36.71 (16.73)	N/A	2.31 (1.86)	mild constipation, 26.53; abdominal pain, 28.57	DRAs (12); topiramate (1); valproate (1); treatment-naive (35)

^aSD, standard deviation; YGTSS, Yale Global Tic Severity Scale; YGTSS-TTS, Yale Global Tic Severity Scale Total Tic Scale (combined motor tic and vocal tic score); GSI, Gastrointestinal Severity Index; TD, tic disorder; PTD, provisional tic disorder; CTD, chronic motor or vocal tic disorder; TS, Tourette syndrome; DRA, dopamine receptor antagonist.