<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD Journal Publishing DTD v2.3 20070202//EN" "journalpublishing.dtd">
<article article-type="research-article" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xml:lang="EN">
<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Pediatr.</journal-id>
<journal-title>Frontiers in Pediatrics</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Pediatr.</abbrev-journal-title>
<issn pub-type="epub">2296-2360</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3389/fped.2025.1636110</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Pediatrics</subject>
<subj-group>
<subject>Original Research</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>The clinical features and initial pharmacotherapeutic options of children with Tic disorders</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author" equal-contrib="yes"><name><surname>Xiang</surname><given-names>Yuxin</given-names></name>
<xref ref-type="author-notes" rid="an1"><sup>&#x2020;</sup></xref><uri xlink:href="https://loop.frontiersin.org/people/3081169/overview"/><role content-type="https://credit.niso.org/contributor-roles/methodology/"/><role content-type="https://credit.niso.org/contributor-roles/formal-analysis/"/><role content-type="https://credit.niso.org/contributor-roles/writing-original-draft/"/><role content-type="https://credit.niso.org/contributor-roles/data-curation/"/></contrib>
<contrib contrib-type="author" equal-contrib="yes"><name><surname>Tong</surname><given-names>Chang</given-names></name>
<xref ref-type="author-notes" rid="an1"><sup>&#x2020;</sup></xref><role content-type="https://credit.niso.org/contributor-roles/data-curation/"/><role content-type="https://credit.niso.org/contributor-roles/writing-original-draft/"/></contrib>
<contrib contrib-type="author"><name><surname>Sun</surname><given-names>Dan</given-names></name>
<uri xlink:href="https://loop.frontiersin.org/people/1284102/overview" />
<role content-type="https://credit.niso.org/contributor-roles/writing-review-editing/"/></contrib>
<contrib contrib-type="author" corresp="yes"><name><surname>Liu</surname><given-names>Zhisheng</given-names></name>
<xref ref-type="corresp" rid="cor1">&#x002A;</xref><role content-type="https://credit.niso.org/contributor-roles/supervision/"/><role content-type="https://credit.niso.org/contributor-roles/writing-review-editing/"/></contrib>
</contrib-group>
<aff><institution>Department of Neurology, Wuhan Children&#x2019;s Hospital, Tongji Medical College, Huazhong University of Science and Technology</institution>, <addr-line>Wuhan</addr-line>, <country>China</country></aff>
<author-notes>
<fn fn-type="edited-by"><p><bold>Edited by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/303120/overview">Renata Rizzo</ext-link>, University of Catania, Italy</p></fn>
<fn fn-type="edited-by"><p><bold>Reviewed by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/2033152/overview">Renato Arruda</ext-link>, University of S&#x00E3;o Paulo, Brazil</p>
<p><ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/315027/overview">Valeria Sajin</ext-link>, Asklepios Klinik St. Georg, Germany</p></fn>
<corresp id="cor1"><label>&#x002A;</label><bold>Correspondence:</bold> Zhisheng Liu <email>liuzhisheng@hust.edu.cn</email></corresp>
<fn fn-type="equal" id="an1"><label><sup>&#x2020;</sup></label><p>These authors have contributed equally to this work</p></fn>
</author-notes>
<pub-date pub-type="epub"><day>17</day><month>09</month><year>2025</year></pub-date>
<pub-date pub-type="collection"><year>2025</year></pub-date>
<volume>13</volume><elocation-id>1636110</elocation-id>
<history>
<date date-type="received"><day>29</day><month>05</month><year>2025</year></date>
<date date-type="accepted"><day>05</day><month>09</month><year>2025</year></date>
</history>
<permissions>
<copyright-statement>&#x00A9; 2025 Xiang, Tong, Sun and Liu.</copyright-statement>
<copyright-year>2025</copyright-year><copyright-holder>Xiang, Tong, Sun and Liu</copyright-holder><license license-type="open-access" xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the <ext-link ext-link-type="uri" xlink:href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution License (CC BY)</ext-link>. The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p></license>
</permissions>
<abstract><sec><title>Purpose</title>
<p>Tic disorders (TD) are common childhood neurodevelopmental conditions, characterized by diverse manifestations, leading to misdiagnosis and delayed therapy. Timely identification of TD and access to care can improve clinical outcomes. This retrospective study characterizes clinical features and initial pharmacotherapy in newly diagnosed pediatric TD.</p>
</sec><sec><title>Method</title>
<p>This retrospective cohort study included 805 newly diagnosed pediatric TD patients. Tic severity was assessed using the Yale Global Tic Severity Scale (YGTSS), with patients stratified into mild (YGTSS scores&#x2009;&#x003C;&#x2009;25), moderate (25&#x2013;50), and severe (&#x003E;50) groups. Chi-square tests/Fisher-exact tests and Wilcoxon rank&#x2014;sum tests compared group differences in baseline characteristics. Multivariate analyses identified factors associated with tic severity, and logistic regression analyses identified predictors of pharmacotherapy initiation.</p>
</sec><sec><title>Results</title>
<p>In 805 subjects, 73.43&#x0025;, 11.18&#x0025; and 15.39&#x0025; were classified into provisional tic disorder, chronic tic disorder, and Tourette syndrome (TS). The prevalence of comorbid attention-deficit/hyperactivity disorder (ADHD) was higher in moderate (21.45&#x0025;) and severe (36.36&#x0025;) groups than in the mild group (15.60&#x0025;). The diagnosis of Tourette syndrome (aOR&#x2009;&#x003D;&#x2009;1.40, 95&#x0025; CI: 1.23&#x2013;160.31), age at onset (aOR&#x2009;&#x003D;&#x2009;1.63, 95&#x0025; CI: 1.22&#x2013;2.18), and age at diagnosis (aOR&#x2009;&#x003D;&#x2009;1.63, 95&#x0025; CI: 1.22&#x2013;2.17), comorbid ADHD (aOR&#x2009;&#x003D;&#x2009;7.12, 95&#x0025; CI: 1.39&#x2013;36.43) were positively associated with greater tic severity. Clonidine patch (CAP) and traditional Chinese medicine (TCM) were the most common choices initial pharmacotherapy in newly diagnosed pediatric TD. Scores of YGTSS, comorbid ADHD predicted treatment initiation.</p>
</sec><sec><title>Conclusions</title>
<p>This study contributed insights into the clinical profiles across tic severity and pharmacotherapeutic approaches in newly diagnosed pediatric TD. The findings highlighted the independent associations between baseline factors and tic severity, as well as the predictors of pharmacotherapy initiation. CAP and TCM served as the most common choices in newly diagnosed pediatric TD.</p>
</sec>
</abstract>
<kwd-group>
<kwd>Tic disorders</kwd>
<kwd>clinical manifestations</kwd>
<kwd>tic severity</kwd>
<kwd>pharmacotherapy initiation</kwd>
<kwd>pediatric patients</kwd>
</kwd-group><contract-num rid="cn001">2021YFC0863700</contract-num><contract-num rid="cn002">2022DCC020</contract-num><contract-sponsor id="cn001">National Key Research and Development Plan</contract-sponsor><contract-sponsor id="cn002">Hubei Provincial Science and Technology Plan Project for Clinical Research Center of Neurodevelopmental Disorders in Children</contract-sponsor><counts>
<fig-count count="1"/>
<table-count count="5"/><equation-count count="0"/><ref-count count="28"/><page-count count="7"/><word-count count="0"/></counts><custom-meta-wrap><custom-meta><meta-name>section-at-acceptance</meta-name><meta-value>Pediatric Neurology</meta-value></custom-meta></custom-meta-wrap>
</article-meta>
</front>
<body><sec id="s1" sec-type="intro"><label>1</label><title>Introduction</title>
<p>Tic disorders (TD) are childhood-onset neurodevelopmental conditions characterized by motor and/or phonic tics (<xref ref-type="bibr" rid="B1">1</xref>). Based on motor/phonic manifestations and courses of tics, TD are classified into three subtypes: provisional tic disorder (PTD), chronic tic disorder (CTD), and Tourette syndrome (TS). TD typically emerge around 5 years of age, peak in severity between 10 and 14 years and often tend to decline in adolescence (<xref ref-type="bibr" rid="B2">2</xref>). The severity of TD varies among individuals. In some cases, TD can impair daily functioning, affecting social interactions and academic performance (<xref ref-type="bibr" rid="B3">3</xref>). A survey shows that approximately 88&#x0025; of patients report TD&#x0027;s negative influence on their daily lives (<xref ref-type="bibr" rid="B4">4</xref>). Severe or frequent tics may cause cervical spine injuries and neurological complications, including disc herniation, myelopathy, and even stroke due to traumatic vascular dissection (e.g., carotid/vertebral arteries) (<xref ref-type="bibr" rid="B5">5</xref>). Functional impairment generally worsens with increasing tic severity (<xref ref-type="bibr" rid="B6">6</xref>). Therefore, accurate diagnoses and timely intervention are essential to alleviate symptoms and reduce the overall disease burden in TD patients (<xref ref-type="bibr" rid="B7">7</xref>).</p>
<p>TD&#x0027;s clinical manifestations often overlap with other diseases, frequently resulting in misdiagnosis and delayed therapy (<xref ref-type="bibr" rid="B8">8</xref>). Indeed, prior studies have indicated a substantial diagnostic delay in TD, with intervals ranging from 3 to 12 years (<xref ref-type="bibr" rid="B8">8</xref>). Moreover, approximately 76&#x0025;&#x2013;90&#x0025; of TD patients have comorbidities, including attention-deficit/hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), oppositional defiant disorder (ODD), sleep problems, and anxiety and depression disorders (<xref ref-type="bibr" rid="B1">1</xref>, <xref ref-type="bibr" rid="B9">9</xref>). The coexistence of comorbidities not only increases the risk of more severe and impairing symptoms but also considerably complicates the diagnostic process (<xref ref-type="bibr" rid="B1">1</xref>, <xref ref-type="bibr" rid="B9">9</xref>).</p>
<p>The comprehensive management for TD comprise pharmacological, behavioral therapies and psychoeducation. Among these, pharmacological interventions have advantages in terms of their accessibility and convenience. Globally, aripiprazole, tiapride and clonidine are frequently recommended (<xref ref-type="bibr" rid="B1">1</xref>, <xref ref-type="bibr" rid="B10">10</xref>, <xref ref-type="bibr" rid="B11">11</xref>). In China, first-line medications for TD consist of antipsychotics, alpha agonists, traditional Chinese medicine (TCM) (<xref ref-type="bibr" rid="B11">11</xref>&#x2013;<xref ref-type="bibr" rid="B13">13</xref>). ChangMaXiFeng Tablets contain traditional Chinese herbs derived from aqueous extracts of Gastrodia (Tianma) and Rhizoma Acori Tatarinowii (Cangpu); ShaoMaZhiJing Granules include Baishao (from Paeonia lactiflora) and Tianma; and JiuWeiXiFeng Granules comprise Gouteng (from Uncaria) and Tianma&#x2014;all these TCM have been approved for TD therapy (<xref ref-type="bibr" rid="B14">14</xref>). In clinical practice, treatment decisions including whether to initiate pharmacotherapy and which agents to use greatly depend on clinicians&#x0027; judgment and guardians&#x0027; preferences (<xref ref-type="bibr" rid="B13">13</xref>). To date, evidence regarding optimal pharmacotherapy for newly diagnosed pediatric patients remains limited, particularly concerning how symptom severity and demographic factors (e.g., age, gender comorbidity) influence pharmacotherapeutic options.</p>
<p>Timely identification of TD and access to evidence&#x2014;based care can improve clinical outcomes (<xref ref-type="bibr" rid="B15">15</xref>). However, existing studies on newly diagnosed pediatric TD populations remain scarce, particularly regarding nuanced clinical characteristics, real-world pharmacotherapy patterns, and the impact of demographic factors on treatment decisions. This retrospective study aims to describe the clinical characteristics and initial pharmacotherapy choices in pediatric patients newly diagnosed with TD, to compare features across different levels of tic severity, and to examine the association between demographic factors and both disease severity and treatment selection.</p>
</sec>
<sec id="s2"><label>2</label><title>Methods and study design</title>
<p>This retrospective cohort study enrolled children aged 4&#x2013;18 years who were newly diagnosed with TD at Wuhan Children&#x0027;s Hospital from October 2022 to October 2024, according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria. Tic severity was assessed using the Yale Global Tic Severity Scale (YGTSS), a well-established gold standard for evaluating TD. The severity of motor and phonic tics is assessed from aspects of their number, frequency, intensity, complexity and interference, as well as the impairment (<xref ref-type="bibr" rid="B16">16</xref>). YGTSS ratings were conducted by trained assessment physicians, all of whom received standardized training on this scale to ensure consistency and minimize subjectivity.</p>
<p>The inclusion criteria were as follows: (1) Diagnosed with TD according to DSM-5 criteria; (2) First visit to the clinic; (3) Aged 4&#x2013;18 years; (4) Complete clinical data. Finally, a total of 805 patients were included in this study.</p>
<p>Demographic information included gender and age. The basic clinical information included age at symptom onset and diagnosis, clinical course (defined as the time interval from tic onset to diagnosis), TD subtypes, symptoms, comorbid ADHD, YGTSS scores, electroencephalogram (EEG) as well as medication options.</p>
<p>Patient data were retrieved from the scientific research data platform of Wuhan Children&#x0027;s Hospital, specifically from the hospital&#x0027;s specialized database for TD. This is a platform with preset safeguards to protect the patients&#x0027; private information. The study was approved by the Medical Ethics Committee of Wuhan Children&#x0027;s Hospital (No. 2025R013-E01) according to <italic>Measures for Ethical Review of Life Sciences and Medical Research Involving Humans in China</italic>, and all patient privacy was strictly protected throughout the research process.</p>
</sec>
<sec id="s3"><label>3</label><title>Statistical analysis</title>
<p>All data were analyzed using <italic>R version 4.4.2</italic>. Categorical variables were presented as frequencies and percentages. Normally distributed continuous variables were presented as mean&#x2009;&#x00B1;&#x2009;standard deviation (SD), while skewed continuous variables were presented as median (25th, 75th percentiles).</p>
<p>Based on YGTSS scores, patients were classified into mild (&#x003C;25), moderate (25&#x2013;50), and severe tic groups (&#x003E;50). Group differences in age at onset, clinical course, age at diagnosis, TD subtypes, tic symptoms, and premonitory tic were compared using continuity correction chi-square tests/Fisher-exact tests and Wilcoxon rank&#x2014;sum tests.</p>
<p>Multivariate analyses were performed to identify factors associated with tic severity, with crude odds ratios (ORs) [95&#x0025; confidence intervals (CIs)] and adjusted ORs (aORs) (95&#x0025; CIs) reported. For the decision to initiate pharmacotherapy, logistic regression was applied to estimate ORs (95&#x0025; CIs) and aORs (95&#x0025; CIs) for initiating pharmacotherapy, providing an overview of clinical/demographic factors associated with the pharmacotherapeutic strategies. All <italic>p</italic>-values were two-tailed, and a <italic>p</italic>&#x2009;&#x003C;&#x2009;0.05 was considered statistically significant. For multiple pairwise comparisons between groups, <italic>p</italic>-values were adjusted using the Bonferroni correction to account for multiple testing. Additionally, we summarized the specific medications prescribed at initial diagnosis, including both monotherapy and combination therapy.</p>
</sec>
<sec id="s4" sec-type="results"><label>4</label><title>Results</title>
<sec id="s4a"><label>4.1</label><title>Demographic and clinical features in pediatric TD patients</title>
<p>A total of 805 patients were included in the study, comprising 659 males and 146 females (male: female&#x2009;&#x003D;&#x2009;4.51:1). For TD subtypes, 73.43&#x0025; (<italic>n</italic>&#x2009;&#x003D;&#x2009;591), 11.18&#x0025; (<italic>n</italic>&#x2009;&#x003D;&#x2009;90), and 15.39&#x0025; (<italic>n</italic>&#x2009;&#x003D;&#x2009;124) were classified into PTD, CTD, and TS, respectively. Among them, 144 cases (17.88&#x0025;) had comorbid ADHD. The median age at diagnosis was 7.51 (6.07, 9.19) years and a median age at onset was 6.87 (5.24, 8.60) years. The median duration from symptom onset to diagnosis was 2.00 (1.00, 12.00) months.</p>
<p>Patients were classified into mild (<italic>n</italic>&#x2009;&#x003D;&#x2009;519, 64.47&#x0025;), moderate (<italic>n</italic>&#x2009;&#x003D;&#x2009;275, 34.16&#x0025;), and severe (<italic>n</italic>&#x2009;&#x003D;&#x2009;11, 1.37&#x0025;) groups based on YGTSS. The five most common tic symptoms were eye blinking/eye rolling (<italic>n</italic>&#x2009;&#x003D;&#x2009;490, 60.87&#x0025;), jaw/lip movement/spitting (<italic>n</italic>&#x2009;&#x003D;&#x2009;202, 25.09&#x0025;), head movement (<italic>n</italic>&#x2009;&#x003D;&#x2009;196, 24.34&#x0025;), throat clearing (<italic>n</italic>&#x2009;&#x003D;&#x2009;190, 23.60&#x0025;), and grunting (<italic>n</italic>&#x2009;&#x003D;&#x2009;138, 17.14&#x0025;). Twenty patients (2.48&#x0025;) had a family history of TD in their first-degree relatives.</p>
<p>Among the patients, 27 (3.35&#x0025;) exhibited EEG abnormalities. Of these, generalized epileptiform discharges were observed in 7 children, focal epileptiform discharges in 19 children, and diffuse slowing in 1 child. The anatomical locations of focal discharges were predominantly in the temporal (<italic>n</italic>&#x2009;&#x003D;&#x2009;9) and central (<italic>n</italic>&#x2009;&#x003D;&#x2009;9) regions.</p>
</sec>
<sec id="s4b"><label>4.2</label><title>Different clinical characteristics among different tic severity groups</title>
<p>No significant difference in gender distribution was observed across the mild, moderate, and severe tic severity groups. The prevalence of PTD diagnosis differed significantly among the groups, with a higher proportion in the mild tic group (74.95&#x0025;) than in the moderate (70.54&#x0025;) and severe (72.27&#x0025;) groups (<italic>&#x03C7;</italic><sup>2</sup>&#x2009;&#x003D;&#x2009;21.61, <italic>p</italic>&#x2009;&#x003C;&#x2009;0.01, Cramer&#x0027;s V&#x2009;&#x003D;&#x2009;0.12) (<xref ref-type="table" rid="T1">Table&#x00A0;1</xref>). The prevalence of comorbid ADHD was higher in moderate (21.45&#x0025;) and severe (36.36&#x0025;) groups than in the mild group (15.60&#x0025;) (<italic>&#x03C7;</italic><sup>2</sup>&#x2009;&#x003D;&#x2009;6.78, <italic>p</italic>&#x2009;&#x003D;&#x2009;0.03, Cramer&#x0027;s V&#x2009;&#x003D;&#x2009;0.09). The median duration from tic onset to diagnosis was 2.00 (0.66, 12.00), 3.00 (1.00, 12.00) and 5.00 (1.66, 9.08) months in mild, moderate, and severe TD groups, respectively (pairwise comparison <italic>p</italic>&#x2009;&#x003C;&#x2009;0.01 for mild vs. moderate).</p>
<table-wrap id="T1" position="float"><label>Table 1</label>
<caption><p>Clinical features of pediatric patients newly diagnosed with tic disorders among the 3 groups.</p></caption>
<table frame="hsides" rules="groups">
<colgroup>
<col align="left"/>
<col align="center"/>
<col align="center"/>
<col align="center"/>
<col align="center"/>
</colgroup>
<thead>
<tr>
<th valign="top" align="left">Median (25th, 75th)/<italic>N</italic> (&#x0025;)</th>
<th valign="top" align="center">Mild tic group (<italic>n</italic>&#x2009;&#x003D;&#x2009;519)</th>
<th valign="top" align="center">Moderate tic group (<italic>n</italic>&#x2009;&#x003D;&#x2009;275)</th>
<th valign="top" align="center">Severe tic group (<italic>n</italic>&#x2009;&#x003D;&#x2009;11)</th>
<th valign="top" align="center"><italic>p</italic> value</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left">Male<xref ref-type="table-fn" rid="table-fn1"><sup>a</sup></xref></td>
<td valign="top" align="center">417 (80.35)</td>
<td valign="top" align="center">232 (84.36)</td>
<td valign="top" align="center">10 (90.90)</td>
<td valign="top" align="center">0.28</td>
</tr>
<tr>
<td valign="top" align="left">Female</td>
<td valign="top" align="center">102 (19.65)</td>
<td valign="top" align="center">43 (15.64)</td>
<td valign="top" align="center">1 (9.10)</td>
<td valign="top" align="center"/>
</tr>
<tr>
<td valign="top" align="left">Age at onset (year)<xref ref-type="table-fn" rid="table-fn2"><sup>b</sup></xref></td>
<td valign="top" align="center">6.94 (5.39, 8.61)</td>
<td valign="top" align="center">6.81 (5.39, 8.49)</td>
<td valign="top" align="center">8.04 (5.94, 9.51)</td>
<td valign="top" align="center">0.35</td>
</tr>
<tr>
<td valign="top" align="left">Clinical course (month)<xref ref-type="table-fn" rid="table-fn2"><sup>b</sup></xref></td>
<td valign="top" align="center">2.00 (0.66, 12.00)</td>
<td valign="top" align="center">3.00 (1.00, 12.00)</td>
<td valign="top" align="center">5.00 (1.66, 9.08)</td>
<td valign="top" align="center">&#x003C;0.01</td>
</tr>
<tr>
<td valign="top" align="left">Age at diagnosis (year)<xref ref-type="table-fn" rid="table-fn2"><sup>b</sup></xref></td>
<td valign="top" align="center">7.50 (6.00, 9.05)</td>
<td valign="top" align="center">7.48 (6.18, 9.54)</td>
<td valign="top" align="center">8.57 (6.97, 10.22)</td>
<td valign="top" align="center">0.14</td>
</tr>
<tr>
<td valign="top" align="left">ADHD<xref ref-type="table-fn" rid="table-fn1"><sup>a</sup></xref></td>
<td valign="top" align="center">81 (15.60)</td>
<td valign="top" align="center">59 (21.45)</td>
<td valign="top" align="center">4 (36.36)</td>
<td valign="top" align="center">0.03</td>
</tr>
<tr>
<td valign="top" align="left">Provisional tic disorder<xref ref-type="table-fn" rid="table-fn1"><sup>a</sup></xref></td>
<td valign="top" align="center">389 (74.95)</td>
<td valign="top" align="center">194 (70.54)</td>
<td valign="top" align="center">8 (72.27)</td>
<td valign="top" align="center" rowspan="3">&#x003C;0.01</td>
</tr>
<tr>
<td valign="top" align="left">Chronic tic disorder</td>
<td valign="top" align="center">70 (13.48)</td>
<td valign="top" align="center">19 (6.90)</td>
<td valign="top" align="center">1 (9.09)</td>
</tr>
<tr>
<td valign="top" align="left">Tourette syndrome</td>
<td valign="top" align="center">60 (11.56)</td>
<td valign="top" align="center">62 (22.54)</td>
<td valign="top" align="center">2 (18.18)</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table-fn1"><label><sup>a</sup></label>
<p>Continuity Correction Chi&#x2014;Square Test.</p></fn>
<fn id="table-fn2"><label><sup>b</sup></label>
<p>Wilcoxon rank-sum test.</p></fn>
<fn id="table-fn3"><p>ADHD, attention-deficit/hyperactivity disorder.</p></fn>
</table-wrap-foot>
</table-wrap>
<p>The prevalence of vocal tics was significantly higher in the moderate TD group (throat clearing: 33.45&#x0025;; grunting: 25.09&#x0025;) than in the mild TD group (throat clearing: 18.49&#x0025;; grunting: 12.52&#x0025;) (pairwise comparison <italic>p</italic>&#x2009;&#x003C;&#x2009;0.01) (<xref ref-type="table" rid="T2">Table&#x00A0;2</xref>).</p>
<table-wrap id="T2" position="float"><label>Table 2</label>
<caption><p>Symptoms of pediatric patients newly diagnosed with tic disorders among the 3 groups.</p></caption>
<table frame="hsides" rules="groups">
<colgroup>
<col align="left"/>
<col align="center"/>
<col align="center"/>
<col align="center"/>
<col align="center"/>
</colgroup>
<thead>
<tr>
<th valign="top" align="left"><italic>N</italic> (&#x0025;)</th>
<th valign="top" align="center">Mild tic group (<italic>n</italic>&#x2009;&#x003D;&#x2009;519)</th>
<th valign="top" align="center">Moderate tic group (<italic>n</italic>&#x2009;&#x003D;&#x2009;275)</th>
<th valign="top" align="center">Severe tic group (<italic>n</italic>&#x2009;&#x003D;&#x2009;11)</th>
<th valign="top" align="center"><italic>p</italic> value</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left">Eye blinking/eye rolling</td>
<td valign="top" align="center">319 (61.46)</td>
<td valign="top" align="center">168 (61.09)</td>
<td valign="top" align="center">3 (27.27)</td>
<td valign="top" align="center">0.07</td>
</tr>
<tr>
<td valign="top" align="left">Jaw/lip movement/spitting</td>
<td valign="top" align="center">130 (25.04)</td>
<td valign="top" align="center">69 (25.09)</td>
<td valign="top" align="center">3 (27.27)</td>
<td valign="top" align="center">0.98</td>
</tr>
<tr>
<td valign="top" align="left">Head movement</td>
<td valign="top" align="center">125 (24.08)</td>
<td valign="top" align="center">69 (25.09)</td>
<td valign="top" align="center">2 (18.18)</td>
<td valign="top" align="center">0.84</td>
</tr>
<tr>
<td valign="top" align="left">Throat clearing</td>
<td valign="top" align="center">96 (18.49)</td>
<td valign="top" align="center">92 (33.45)</td>
<td valign="top" align="center">2 (18.18)</td>
<td valign="top" align="center">&#x003C;0.05</td>
</tr>
<tr>
<td valign="top" align="left">Grunting</td>
<td valign="top" align="center">65 (12.52)</td>
<td valign="top" align="center">69 (25.09)</td>
<td valign="top" align="center">4 (36.36)</td>
<td valign="top" align="center">&#x003C;0.05</td>
</tr>
</tbody>
</table>
</table-wrap>
<p>Multivariate analyses revealed that the diagnosis of Tourette syndrome (aOR&#x2009;&#x003D;&#x2009;1.40, 95&#x0025; CI: 1.23&#x2013;160.31), age at onset (aOR&#x2009;&#x003D;&#x2009;1.63, 95&#x0025; CI: 1.22&#x2013;2.18), and age at diagnosis (aOR&#x2009;&#x003D;&#x2009;1.63, 95&#x0025; CI: 1.22&#x2013;2.17) were positively associated with greater tic severity. The prevalence of comorbid ADHD demonstrated a positive association with higher tic severity (aOR&#x2009;&#x003D;&#x2009;7.12, 95&#x0025; CI: 1.39&#x2013;36.43) (<xref ref-type="table" rid="T3">Table&#x00A0;3</xref>).</p>
<table-wrap id="T3" position="float"><label>Table 3</label>
<caption><p>Multivariate analyses of the association between demographic factors and tic severity.</p></caption>
<table frame="hsides" rules="groups">
<colgroup>
<col align="left"/>
<col align="center"/>
<col align="center"/>
</colgroup>
<thead>
<tr>
<th valign="top" align="left">Demographic factors</th>
<th valign="top" align="center">OR (95&#x0025; CI)</th>
<th valign="top" align="center">aOR (95&#x0025; CI)</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left">Male<sup>a,</sup>&#x002A;</td>
<td valign="top" align="center">4.5 (0.86&#x2013;15.61)</td>
<td valign="top" align="center">2.49 (0.46&#x2013;12.55)</td>
</tr>
<tr>
<td valign="top" align="left">Clinical course<xref ref-type="table-fn" rid="table-fn5"><sup>b</sup></xref></td>
<td valign="top" align="center">1.08 (1.02&#x2013;1.14)</td>
<td valign="top" align="center">1.00 (0.98&#x2013;1.01)</td>
</tr>
<tr>
<td valign="top" align="left">Chronic tic disorder<sup>c,</sup>&#x002A;&#x002A;</td>
<td valign="top" align="center">0.14 (0.09&#x2013;1.09)</td>
<td valign="top" align="center">0.03 (0.01&#x2013;0.41)</td>
</tr>
<tr>
<td valign="top" align="left">Tourette syndrome<sup>c,</sup>&#x002A;&#x002A;</td>
<td valign="top" align="center">72.96 (12.26&#x2013;421.26)</td>
<td valign="top" align="center">1.40 (1.23&#x2013;160.31)</td>
</tr>
<tr>
<td valign="top" align="left">Attention-deficit/hyperactivity disorder<xref ref-type="table-fn" rid="table-fn7"><sup>d</sup></xref></td>
<td valign="top" align="center">12.16 (2.32&#x2013;63.49)</td>
<td valign="top" align="center">7.12 (1.39&#x2013;36.43)</td>
</tr>
<tr>
<td valign="top" align="left">Age at onset<xref ref-type="table-fn" rid="table-fn8"><sup>e</sup></xref></td>
<td valign="top" align="center">1.47 (1.11&#x2013;1.96)</td>
<td valign="top" align="center">1.63 (1.22&#x2013;2.18)</td>
</tr>
<tr>
<td valign="top" align="left">Age at diagnosis<xref ref-type="table-fn" rid="table-fn8"><sup>e</sup></xref></td>
<td valign="top" align="center">1.76 (1.33&#x2013;2.32)</td>
<td valign="top" align="center">1.63 (1.22&#x2013;2.17)</td>
</tr>
<tr>
<td valign="top" align="left">Premonitory urge<xref ref-type="table-fn" rid="table-fn9"><sup>f</sup></xref></td>
<td valign="top" align="center">0.16 (0.01&#x2013;2.79)</td>
<td valign="top" align="center">0.12 (0.01&#x2013;2.09)</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table-fn4"><label><sup>a</sup></label>
<p>Adjusted clinical course, diagnoses, ADHD (attention-deficit/hyperactivity disorder), age at diagnosis, premonitory urge.</p></fn>
<fn id="table-fn5"><label><sup>b</sup></label>
<p>Adjusted gender, diagnoses, ADHD, age at diagnosis, premonitory urge.</p></fn>
<fn id="table-fn6"><label><sup>c</sup></label>
<p>Adjusted gender, clinical course, ADHD, age at diagnosis, premonitory urge.</p></fn>
<fn id="table-fn7"><label><sup>d</sup></label>
<p>Adjusted gender, clinical course, diagnoses, age at diagnosis, premonitory urge.</p></fn>
<fn id="table-fn8"><label><sup>e</sup></label>
<p>Adjusted gender, clinical course, ADHD, diagnoses, premonitory urge.</p></fn>
<fn id="table-fn9"><label><sup>f</sup></label>
<p>Adjusted gender, clinical course, diagnoses, ADHD, age at diagnosis.</p></fn>
<fn id="table-fn10"><label>&#x002A;</label>
<p>The reference group is the female group.</p></fn>
<fn id="table-fn11"><label>&#x002A;&#x002A;</label>
<p>The reference group is the provisional tic disorder group.</p></fn>
</table-wrap-foot>
</table-wrap>
</sec>
<sec id="s4c"><label>4.3</label><title>The initial pharmacotherapy options of TD</title>
<p>Pharmacotherapy was initiated in 75.4&#x0025; (<italic>n</italic>&#x2009;&#x003D;&#x2009;607) of patients at initial TD diagnosis. Among these, 161 (26.52&#x0025;) received combination therapy, and 446 (73.48&#x0025;) adopted monotherapy. Within the monotherapy group, clonidine adhesive patch (CAP) constituted the primary choice (<italic>n</italic>&#x2009;&#x003D;&#x2009;270, 60.53&#x0025;), followed by TCM (<italic>n</italic>&#x2009;&#x003D;&#x2009;112, 25.11&#x0025;) (<xref ref-type="table" rid="T4">Table&#x00A0;4</xref>). Within prespecified age subgroups (&#x003C;6 years, 6&#x2013;12 years, &#x003E;12 years; <xref ref-type="fig" rid="F1">Figure&#x00A0;1</xref>), TCM and CAP remained the most common options (though <italic>p</italic>&#x2009;&#x003D;&#x2009;0.21). In the combination therapy group, the majority were prescribed CAP&#x2009;&#x002B;&#x2009;TCM (<italic>n</italic>&#x2009;&#x003D;&#x2009;83, 51.56&#x0025;), followed by CAP combined with antipsychotics (<italic>n</italic>&#x2009;&#x003D;&#x2009;43, 26.71&#x0025;).</p>
<table-wrap id="T4" position="float"><label>Table 4</label>
<caption><p>Pharmacotherapy choices for pediatric patients newly diagnosed with tic disorders.</p></caption>
<table frame="hsides" rules="groups">
<colgroup>
<col align="left"/>
<col align="center"/>
<col align="center"/>
</colgroup>
<thead>
<tr>
<th valign="top" align="left">Monotherapy group (<italic>n</italic>&#x2009;&#x003D;&#x2009;446)</th>
<th valign="top" align="center">Frequency (N)</th>
<th valign="top" align="center">Percentage (&#x0025;)</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left">CAP</td>
<td valign="top" align="center">270</td>
<td valign="top" align="center">60.53</td>
</tr>
<tr>
<td valign="top" align="left">TCM</td>
<td valign="top" align="center">112</td>
<td valign="top" align="center">25.11</td>
</tr>
<tr>
<td valign="top" align="left">Aripiprazole</td>
<td valign="top" align="center">33</td>
<td valign="top" align="center">7.40</td>
</tr>
<tr>
<td valign="top" align="left">Tiapride</td>
<td valign="top" align="center">31</td>
<td valign="top" align="center">6.96</td>
</tr>
<tr>
<td valign="top" align="left" colspan="3">The combined therapy group (<italic>n</italic>&#x2009;&#x003D;&#x2009;161)</td>
</tr>
<tr>
<td valign="top" align="left">CAP&#x2009;&#x002B;&#x2009;TCM</td>
<td valign="top" align="center">83</td>
<td valign="top" align="center">51.56</td>
</tr>
<tr>
<td valign="top" align="left">CAP&#x2009;&#x002B;&#x2009;antipsychotic</td>
<td valign="top" align="center">43</td>
<td valign="top" align="center">26.71</td>
</tr>
<tr>
<td valign="top" align="left">TCM&#x2009;&#x002B;&#x2009;antipsychotic</td>
<td valign="top" align="center">14</td>
<td valign="top" align="center">8.70</td>
</tr>
<tr>
<td valign="top" align="left">Others</td>
<td valign="top" align="center">21</td>
<td valign="top" align="center">13.03</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table-fn12"><p>CAP, clonidine adhesive patch; TCM, traditional Chinese medicine.</p></fn>
</table-wrap-foot>
</table-wrap>
<fig id="F1" position="float"><label>Figure 1</label>
<caption><p>In the monotherapy group, the proportion each medication of age groups. CAP, clonidine adhesive patches; TCM, traditional Chinese medicine.</p></caption>
<graphic mimetype="image" mime-subtype="tiff" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="fped-13-1636110-g001.tif"><alt-text content-type="machine-generated">For ages under six: CAP 55.33%, Tiapride 6.80%, Aripiprazole 5.83%, TCM 32.04%. Ages six to twelve: CAP 62.96%, Tiapride 6.48%, Aripiprazole 7.41%, TCM 23.15%. Ages twelve and above: CAP 47.37%, Tiapride 15.79%, Aripiprazole 15.79%, TCM 21.05%.</alt-text>
</graphic>
</fig>
<p>Logistic regression analysis was used to identify the potential factors associated with initiating pharmacological intervention at initial TD diagnosis. The YGTSS score was associated with starting pharmacological treatment (total score: aOR&#x2009;&#x003D;&#x2009;1.06, 95&#x0025; CI: 1.04&#x2013;1.08; motor score: aOR&#x2009;&#x003D;&#x2009;1.04, 95&#x0025; CI: 1.01&#x2013;1.09; vocal score: aOR&#x2009;&#x003D;&#x2009;1.09, 95&#x0025; CI: 1.05&#x2013;1.13; impair score: aOR&#x2009;&#x003D;&#x2009;1.04, 95&#x0025; CI: 1.01&#x2013;1.08). The comorbid ADHD was related with the odds of starting pharmacotherapy (aOR&#x2009;&#x003D;&#x2009;1.82, 95&#x0025; CI: 1.09&#x2013;3.04) (<xref ref-type="table" rid="T5">Table&#x00A0;5</xref>).</p>
<table-wrap id="T5" position="float"><label>Table 5</label>
<caption><p>The association between demographic factors and the option of starting pharmacological treatment.</p></caption>
<table frame="hsides" rules="groups">
<colgroup>
<col align="left"/>
<col align="center"/>
<col align="center"/>
</colgroup>
<thead>
<tr>
<th valign="top" align="left">Demographic factors</th>
<th valign="top" align="center">OR (95&#x0025; CI)</th>
<th valign="top" align="center">aOR (95&#x0025; CI)</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left">Total score of YGTSS<xref ref-type="table-fn" rid="table-fn13"><sup>a</sup></xref></td>
<td valign="top" align="center">1.07 (1.04&#x2013;1.09)</td>
<td valign="top" align="center">1.06 (1.04&#x2013;1.08)</td>
</tr>
<tr>
<td valign="top" align="left">Motor score of YGTSS<xref ref-type="table-fn" rid="table-fn13"><sup>a</sup></xref></td>
<td valign="top" align="center">1.04 (1.00&#x2013;1.09)</td>
<td valign="top" align="center">1.04 (1.01&#x2013;1.09)</td>
</tr>
<tr>
<td valign="top" align="left">Vocal score of YGTSS<xref ref-type="table-fn" rid="table-fn13"><sup>a</sup></xref></td>
<td valign="top" align="center">1.10 (1.06&#x2013;1.14)</td>
<td valign="top" align="center">1.09 (1.05&#x2013;1.13)</td>
</tr>
<tr>
<td valign="top" align="left">Impair score of YGTSS<xref ref-type="table-fn" rid="table-fn13"><sup>a</sup></xref></td>
<td valign="top" align="center">1.05 (1.02&#x2013;1.09)</td>
<td valign="top" align="center">1.04 (1.01&#x2013;1.08)</td>
</tr>
<tr>
<td valign="top" align="left">Clinical course<xref ref-type="table-fn" rid="table-fn14"><sup>b</sup></xref></td>
<td valign="top" align="center">1.02 (1.01&#x2013;1.04)</td>
<td valign="top" align="center">1.00 (0.99&#x2013;1.01)</td>
</tr>
<tr>
<td valign="top" align="left">Age at diagnosis<xref ref-type="table-fn" rid="table-fn15"><sup>c</sup></xref></td>
<td valign="top" align="center">1.12 (1.04&#x2013;1.21)</td>
<td valign="top" align="center">1.06 (0.98&#x2013;1.15)</td>
</tr>
<tr>
<td valign="top" align="left">Chronic tic disorder<sup>d,</sup>&#x002A;</td>
<td valign="top" align="center">1.12 (0.67&#x2013;1.87)</td>
<td valign="top" align="center">0.89 (0.44&#x2013;1.79)</td>
</tr>
<tr>
<td valign="top" align="left">Tourette syndrome<sup>d,</sup>&#x002A;</td>
<td valign="top" align="center">3.30 (1.81&#x2013;6.03)</td>
<td valign="top" align="center">1.87 (0.84&#x2013;4.17)</td>
</tr>
<tr>
<td valign="top" align="left">Male<sup>e,</sup>&#x002A;&#x002A;</td>
<td valign="top" align="center">1.07 (0.71&#x2013;1.61)</td>
<td valign="top" align="center">0.90 (0.59&#x2013;1.39)</td>
</tr>
<tr>
<td valign="top" align="left">Attention-deficit/hyperactivity disorder<xref ref-type="table-fn" rid="table-fn19"><sup>f</sup></xref></td>
<td valign="top" align="center">2.19 (1.33&#x2013;3.59)</td>
<td valign="top" align="center">1.82 (1.09&#x2013;3.04)</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table-fn13"><label><sup>a</sup></label>
<p>Adjusted clinical course, age at diagnosis, diagnoses, gender, ADHD (attention-deficit/hyperactivity disorder).</p></fn>
<fn id="table-fn14"><label><sup>b</sup></label>
<p>Adjusted total score of YGTSS, age at diagnosis, diagnoses, gender, ADHD.</p></fn>
<fn id="table-fn15"><label><sup>c</sup></label>
<p>Adjusted total score of YGTSS, clinical course, diagnoses, gender, ADHD.</p></fn>
<fn id="table-fn16"><label><sup>d</sup></label>
<p>Adjusted total score of YGTSS, clinical course, age at diagnosis, gender, ADHD.</p></fn>
<fn id="table-fn17"><label><sup>e</sup></label>
<p>Adjusted total score of YGTSS, clinical course, age of diagnosis, diagnoses.</p></fn>
<fn id="table-fn18"><p>ADHD.</p></fn>
<fn id="table-fn19"><label><sup>f</sup></label>
<p>Adjusted total score of YGTSS, clinical course, age at diagnosis, diagnoses, gender.</p></fn>
<fn id="table-fn20"><label>&#x002A;</label>
<p>The reference group is the provisional tic disorder group.</p></fn>
<fn id="table-fn21"><label>&#x002A;&#x002A;</label>
<p>The reference group is the female group.</p></fn>
<fn id="table-fn22"><p>YGTSS, Yale Global Tic Severity Scale.</p></fn>
</table-wrap-foot>
</table-wrap>
<p>Tic severity stratified analysis results showed a clear gradient: pharmacological treatment was used in 100&#x0025; of severe, 86.9&#x0025; of moderate, and 68.2&#x0025; of mild tic severity group cases (<italic>&#x03C7;</italic><sup>2</sup>&#x2009;&#x003D;&#x2009;37.26, <italic>p</italic>&#x2009;&#x003C;&#x2009;0.01, Cramer&#x0027;s V&#x2009;&#x003D;&#x2009;0.215). Combination therapy was more prevalent in moderate (32.21&#x0025;) and severe (45.45&#x0025;) groups compared with mild (21.46&#x0025;) (<italic>&#x03C7;</italic><sup>2</sup>&#x2009;&#x003D;&#x2009;10.69, <italic>p</italic>&#x2009;&#x003C;&#x2009;0.01, Cramer&#x0027;s V&#x2009;&#x003D;&#x2009;0.13).</p>
</sec>
</sec>
<sec id="s5" sec-type="discussion"><label>5</label><title>Discussion</title>
<p>TD are common neurodevelopmental conditions with marked variability. It is estimated that approximately 73&#x0025; of patients are initially misdiagnosed, underscoring the importance of early and accurate diagnosis for initiating timely interventions (<xref ref-type="bibr" rid="B7">7</xref>, <xref ref-type="bibr" rid="B8">8</xref>). TD management requires personalized strategies, with decisions based on guardians&#x0027; preferences, comorbidities, age, tic severity, clinician judgment, expertise, and regional guidelines (<xref ref-type="bibr" rid="B17">17</xref>). However, relevant evidence remains limited.</p>
<p>Clinically, due to subtle or atypical early symptoms, many pediatric patients initially consult other departments such as ophthalmology or otolaryngology&#x2014;before going to neurology. Prior studies have shown that tic symptoms often originate in the face and head (<xref ref-type="bibr" rid="B8">8</xref>, <xref ref-type="bibr" rid="B14">14</xref>). According to Park&#x0027;s research (involving 117 pediatric patients), the most common symptoms in TD are eye blinking (50.40&#x0025;) followed by jaw/lip movement (29.40&#x0025;) and throat clearing (29.40&#x0025;) (<xref ref-type="bibr" rid="B8">8</xref>). Similarly, in Nilles et al&#x0027; study (involving 203 pediatric and adult patients), the most common symptoms are eye blinking (57&#x0025;), head tics (51&#x0025;), eye rolling (48&#x0025;), mouth movements (46&#x0025;), and throat clearing (42&#x0025;) (<xref ref-type="bibr" rid="B18">18</xref>). Another study shows that ocular tics occur in over 90&#x0025; of individuals with TS (<xref ref-type="bibr" rid="B19">19</xref>). Consistent with these reports, our research also find eye blinking/eye rolling to be the most common symptoms (60.87&#x0025;). These findings suggest that although the specific presentation of TD may vary across populations, motor tics predominantly affect the head and face, with eye-related movements being most common (typically &#x003E;50&#x0025;), while throat clearing represents a frequent vocal tic. That is the reason why many patients first seek medical treatment at the ophthalmology or otolaryngology department. Therefore, in children presenting with chief complaints like repetitive eye blinking or throat clearing, clinicians should consider the possibility of TD, and evaluate for additional tic-related symptoms to reduce the risk of misdiagnosis or delayed diagnosis.</p>
<p>&#x00A0;TD patients frequently present with comorbid psychiatric conditions, significantly impairing quality of patient life. ADHD is the most prevalent comorbidity, affecting approximately 20&#x0025; of TD patients and 50&#x0025;&#x2013;60&#x0025; of those with TS (<xref ref-type="bibr" rid="B20">20</xref>, <xref ref-type="bibr" rid="B21">21</xref>). In our study, comorbid ADHD is more prevalent in severe (36.60&#x0025;) and moderate (21.45&#x0025;) TD groups compared to the mild group (15.60&#x0025;). Additionally, ADHD is associated with increased tic severity (aOR&#x2009;&#x003D;&#x2009;7.12, 95&#x0025;CI: 1.39&#x2013;36.43). In fact, compared with TD patients without ADHD, patients with TD and co-occurring ADHD also have greater functional impairment (<xref ref-type="bibr" rid="B22">22</xref>). And Cols et al. find that ADHD is a strong risk factor for tic persistence (OR&#x2009;&#x003D;&#x2009;3.35, 95&#x0025; CI: 2.82&#x2013;3.99) (<xref ref-type="bibr" rid="B23">23</xref>). Clinically, these comorbidities not only complicate the diagnosis of TD but also contribute to impairments in academic performance and social functioning, thereby diminishing quality of life for both patients and their families. Notably, in our study, the comorbid ADHD is even seemingly related with the odds of initiating pharmacotherapy of TD (aOR&#x2009;&#x003D;&#x2009;1.82, 95&#x0025; CI: 1.09&#x2013;3.04). Given the substantial impact of ADHD comorbidity, clinicians may consider addressing ADHD alongside TD in such patients. In Japan, most clinicians indicate atomoxetine as the first-line medication for comorbid ADHD and extended-release guanfacine has been approved for tics in children with ADHD (<xref ref-type="bibr" rid="B10">10</xref>). US guidelines suggest that clonidine, methylphenidate, guanfacine, and combination therapies (e.g., clonidine plus methylphenidate) may effectively reduce both tic severity and ADHD symptoms (<xref ref-type="bibr" rid="B11">11</xref>).</p>
<p>EEG is a sensitive tool for monitoring abnormal brain activity and plays a vital role in the diagnosis of paroxysmal neurological conditions. It is also well-suited for assessing cerebral function in children with TD (<xref ref-type="bibr" rid="B24">24</xref>). In our study, abnormal EEG findings&#x2014;predominantly epileptiform discharges&#x2014;were observed in 27 patients (3.35&#x0025;), though these discharges did not occur synchronously with tic episodes. Some researchers propose that such abnormalities may reflect underlying neural dysfunction and disrupted brain network activity (<xref ref-type="bibr" rid="B25">25</xref>). So, this raises an important question: could the presence of non-specific epileptiform discharges indicate functional impairments in cortical regions responsible for suppressing involuntary motor and vocal tics? However, relevant research supporting this hypothesis is currently limited. In the future, investigations can be conducted into the mechanism of non-specific discharges in children with TD, and even combined with the prognosis of TD.</p>
<p>Pharmacological intervention remains the most common approach for tic therapy. However, the decision to initiate treatment and selection of specific modalities rely on clinicians&#x0027; expertise and caregiver preferences. Meanwhile, international clinical recommendations for pharmacotherapy of TD vary slightly across regions. A Japanese consensus suggests aripiprazole as the first-line medication and risperidone as the second-line option for TD (<xref ref-type="bibr" rid="B10">10</xref>). A survey of Canadian physicians indicates that aripiprazole, risperidone, and clonidine are the most frequently prescribed medications for managing TD (<xref ref-type="bibr" rid="B26">26</xref>). In contrast, European guidelines recommend aripiprazole as the first-line treatment, with risperidone and tiapride designated as second-line medications (<xref ref-type="bibr" rid="B17">17</xref>). Wang et al. conduct a study showing that for patients under 6 years old, TCM and CAP are the most commonly prescribed medications, and the utilization of antipsychotics presents an upward trend as age increased (<xref ref-type="bibr" rid="B11">11</xref>). In our study, TCM and CAP are the most common choices across all age groups. This discrepancy may be attributed to differences in study populations: Wang et al.&#x0027;s cohort included both newly diagnosed and previously treated children&#x2014;some of whom may have switched to antipsychotics after CAP/TCM failed (<xref ref-type="bibr" rid="B11">11</xref>). Moreover, in this study, the sample sizes of the age groups under 6 years old and 12 years old and above are relatively small. Therefore, these prescribing trends may not fully reflect broader real-world patterns.</p>
<p>Notably, antipsychotics such as aripiprazole and tiapride&#x2014;internationally proven as first-line treatments for TD&#x2014;have a low usage rate among newly diagnosed pediatric TD patients in this study. This may be attributed to the fact that all participants in the study were newly diagnosed. In China, many parents may be reluctant to use oral Western medicine, especially in the early stages of the disease, when they tend to try TCM instead. Additionally, the package insert for aripiprazole tablets in China does not list TD as an indication (only schizophrenia is included), which may make it hard for some families to accept.</p>
<p>Both alpha2-adrenergic receptor agonists, antipsychotics and TCM have been approved for TD therapy for their efficacy and safety. However, questions still remain to be answered: when to initiate pharmacotherapy and how to select specific agents? A meta-analysis points that the preference of clinicians and caregivers impact medicine prescription (<xref ref-type="bibr" rid="B27">27</xref>). Prospective studies are limited due to TD&#x0027;s long-term course. While our study identifies baseline factors associated with TD severity (e.g., ADHD comorbidity, tic duration), Ricketts et al. further showed that gender and childhood tic severity predict adult tic severity (<xref ref-type="bibr" rid="B28">28</xref>). Future research should explore additional modifiable risk factors to refine personalized treatment algorithms.</p>
<p>This study has several limitations that should be considered. First, as a single-center retrospective study, the generalizability of the findings may be limited, particularly to populations in different geographic regions or health care systems with distinct diagnostic and treatment protocols. Furthermore, this observation is only applicable to the specific context of clinical practice in China, and we should clarify that there are significant differences in treatment options and regulatory environments across different regions. Additionally, due to the small sample size in some subgroups, formal sensitivity analysis was not feasible; thus, we were unable to control for potential selection or prescription bias in these comparisons, which merits attention. Second, the small number of severe TD cases (<italic>n</italic>&#x2009;&#x003D;&#x2009;11) may introduce bias and reduce the reliability of findings within this subgroup. Third, although TD is commonly associated with various comorbidities such as OCD and anxiety/depressive disorders, this study focused solely on ADHD, which limits further exploration of the comprehensive relationship between TD and their comorbidities. These limitations highlight the need for multicenter, prospective studies with larger sample sizes and even longer follow-up periods to corroborate our findings and enhance the generalizability of the results.</p>
</sec>
<sec id="s6" sec-type="conclusions"><label>6</label><title>Conclusions</title>
<p>In summary, this study contributes insights into the clinical profiles across tic severity and pharmacotherapeutic approaches in newly diagnosed pediatric TD. We emphasize the independent associations between baseline factors and tic severity, as well as the predictors of pharmacotherapy initiation. CAP and TCM serve as the most common choices in newly diagnosed pediatric TD.</p>
</sec>
</body>
<back>
<sec id="s7" sec-type="data-availability"><title>Data availability statement</title>
<p>The data analyzed in this study is subject to the following licenses/restrictions: The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request at <email>liuzhisheng@hust.edu.cn</email>. Requests to access these datasets should be directed to <email>liuzhisheng@hust.edu.cn</email>.</p>
</sec>
<sec id="s8" sec-type="ethics-statement"><title>Ethics statement</title>
<p>The studies involving humans were approved by Ethics Committee of Wuhan Children&#x0027;s Hospital. The studies were conducted in accordance with the local legislation and institutional requirements. Written informed consent for participation was not required from the participants or the participants&#x0027; legal guardians/next of kin in accordance with the national legislation and institutional requirements.</p>
</sec>
<sec id="s9" sec-type="author-contributions"><title>Author contributions</title>
<p>YX: Methodology, Formal analysis, Writing &#x2013; original draft, Data curation. CT: Data curation, Writing &#x2013; original draft. DS: Writing &#x2013; review &#x0026; editing. ZL: Supervision, Writing &#x2013; review &#x0026; editing.</p>
</sec>
<sec id="s10" sec-type="funding-information"><title>Funding</title>
<p>The author(s) declare that financial support was received for the research and/or publication of this article. National Key Research and Development Plan (2021YFC0863700); Hubei Provincial Science and Technology Plan Project for Clinical Research Center of Neurodevelopmental Disorders in Children (2022DCC020).</p>
</sec>
<sec id="s11" sec-type="COI-statement"><title>Conflict of interest</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec id="s12" sec-type="ai-statement"><title>Generative AI statement</title>
<p>The author(s) declare that no Generative AI was used in the creation of this manuscript.</p>
<p>Any alternative text (alt text) provided alongside figures in this article has been generated by Frontiers with the support of artificial intelligence and reasonable efforts have been made to ensure accuracy, including review by the authors wherever possible. If you identify any issues, please contact us.</p>
</sec>
<sec id="s13" sec-type="disclaimer"><title>Publisher&#x0027;s note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
<ref-list><title>References</title>
<ref id="B1"><label>1.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Breton</surname><given-names>Z</given-names></name><name><surname>Denis</surname><given-names>P</given-names></name><name><surname>Gousse</surname><given-names>V</given-names></name><name><surname>Hartmann</surname><given-names>A</given-names></name></person-group>. <article-title>The diagnostic and therapeutic journey of Tourette syndrome: thematic analysis of the difficulties experienced by parents of patients</article-title>. <source>Rev Neurol</source>. (<year>2025</year>) <volume>181</volume>(<issue>6</issue>):<fpage>544</fpage>&#x2013;<lpage>55</lpage>. <pub-id pub-id-type="doi">10.1016/j.neurol.2025.03.011</pub-id><pub-id pub-id-type="pmid">40234118</pub-id></citation></ref>
<ref id="B2"><label>2.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Jurgen</surname><given-names>BO</given-names></name><name><surname>Greenberg</surname><given-names>EL</given-names></name></person-group>. <article-title>Pharmacotherapy for Tourette syndrome</article-title>. <source>Psychiatr Clin North Am</source>. (<year>2025</year>) <volume>48</volume>(<issue>1</issue>):<fpage>91</fpage>&#x2013;<lpage>107</lpage>. <pub-id pub-id-type="doi">10.1016/j.psc.2024.08.008</pub-id><pub-id pub-id-type="pmid">39880518</pub-id></citation></ref>
<ref id="B3"><label>3.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Fernandez de la Cruz</surname><given-names>L</given-names></name><name><surname>Isomura</surname><given-names>K</given-names></name><name><surname>Kuja-Halkola</surname><given-names>R</given-names></name><name><surname>Lichtenstein</surname><given-names>P</given-names></name><name><surname>Larsson</surname><given-names>H</given-names></name><name><surname>Chang</surname><given-names>Z</given-names></name><etal/></person-group> <article-title>All-cause and cause-specific mortality in tourette syndrome and chronic tic disorder</article-title>. <source>Mov Disord</source>. (<year>2025</year>) <volume>40</volume>(<issue>2</issue>):<fpage>335</fpage>&#x2013;<lpage>44</lpage>. <pub-id pub-id-type="doi">10.1002/mds.30084</pub-id><pub-id pub-id-type="pmid">39679818</pub-id></citation></ref>
<ref id="B4"><label>4.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Storch</surname><given-names>EA</given-names></name><name><surname>Merlo</surname><given-names>LJ</given-names></name><name><surname>Lack</surname><given-names>C</given-names></name><name><surname>Milsom</surname><given-names>VA</given-names></name><name><surname>Geffken</surname><given-names>GR</given-names></name><name><surname>Goodman</surname><given-names>WK</given-names></name><etal/></person-group> <article-title>Quality of life in youth with Tourette&#x2019;s syndrome and chronic tic disorder</article-title>. <source>J Clin Child Adolesc Psychol</source>. (<year>2007</year>) <volume>36</volume>(<issue>2</issue>):<fpage>217</fpage>&#x2013;<lpage>27</lpage>. <pub-id pub-id-type="doi">10.1080/15374410701279545</pub-id><pub-id pub-id-type="pmid">17484694</pub-id></citation></ref>
<ref id="B5"><label>5.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Isung</surname><given-names>J</given-names></name><name><surname>Isomura</surname><given-names>K</given-names></name><name><surname>Larsson</surname><given-names>H</given-names></name><name><surname>Sidorchuk</surname><given-names>A</given-names></name><name><surname>Fernandez de la Cruz</surname><given-names>L</given-names></name><name><surname>Mataix-Cols</surname><given-names>D</given-names></name></person-group>. <article-title>Association of Tourette syndrome and chronic tic disorder with cervical spine disorders and related neurological complications</article-title>. <source>JAMA Neurol</source>. (<year>2021</year>) <volume>78</volume>(<issue>10</issue>):<fpage>1205</fpage>&#x2013;<lpage>11</lpage>. <pub-id pub-id-type="doi">10.1001/jamaneurol</pub-id><pub-id pub-id-type="pmid">34424277</pub-id></citation></ref>
<ref id="B6"><label>6.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Hu</surname><given-names>SJ</given-names></name><name><surname>Li</surname><given-names>Y</given-names></name><name><surname>Yang</surname><given-names>QH</given-names></name><name><surname>Yang</surname><given-names>K</given-names></name><name><surname>Jun</surname><given-names>JH</given-names></name><name><surname>Cui</surname><given-names>YH</given-names></name><etal/></person-group> <article-title>Family functioning mediation in tic severity and quality of life for children with Tourette syndrome</article-title>. <source>World J Psychiatry</source>. (<year>2024</year>) <volume>14</volume>(<issue>11</issue>):<fpage>1641</fpage>&#x2013;<lpage>51</lpage>. <pub-id pub-id-type="doi">10.5498/wjp.v14.i11.1641</pub-id><pub-id pub-id-type="pmid">39564170</pub-id></citation></ref>
<ref id="B7"><label>7.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Johnson</surname><given-names>KA</given-names></name><name><surname>Worbe</surname><given-names>Y</given-names></name><name><surname>Foote</surname><given-names>KD</given-names></name><name><surname>Butson</surname><given-names>CR</given-names></name><name><surname>Gunduz</surname><given-names>A</given-names></name><name><surname>Okun</surname><given-names>MS</given-names></name></person-group>. <article-title>Tourette syndrome: clinical features, pathophysiology, and treatment</article-title>. <source>Lancet Neurol</source>. (<year>2023</year>) <volume>22</volume>(<issue>2</issue>):<fpage>147</fpage>&#x2013;<lpage>58</lpage>. <pub-id pub-id-type="doi">10.1016/S1474-4422(22)00303-9</pub-id><pub-id pub-id-type="pmid">36354027</pub-id></citation></ref>
<ref id="B8"><label>8.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Park</surname><given-names>EG</given-names></name><name><surname>Kim</surname><given-names>YH</given-names></name></person-group>. <article-title>Clinical features and neuropsychiatric comorbidities in pediatric patients with tic disorders: a retrospective chart review study from South Korea</article-title>. <source>BMC Psychiatry</source>. (<year>2021</year>) <volume>21</volume>(<issue>1</issue>):<fpage>14</fpage>. <pub-id pub-id-type="doi">10.1186/s12888-020-03014-z</pub-id><pub-id pub-id-type="pmid">33413251</pub-id></citation></ref>
<ref id="B9"><label>9.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Claudio-Campos</surname><given-names>K</given-names></name><name><surname>Stevens</surname><given-names>D</given-names></name><name><surname>Koo</surname><given-names>SW</given-names></name><name><surname>Valko</surname><given-names>A</given-names></name><name><surname>Bienvenu</surname><given-names>OJ</given-names></name><name><surname>Budman</surname><given-names>CB</given-names></name><etal/></person-group> <article-title>Is persistent motor or vocal tic disorder a milder form of Tourette syndrome?</article-title> <source>Mov Disord</source>. (<year>2021</year>) <volume>36</volume>(<issue>8</issue>):<fpage>1899</fpage>&#x2013;<lpage>910</lpage>. <pub-id pub-id-type="doi">10.1002/mds.28593</pub-id><pub-id pub-id-type="pmid">33942911</pub-id></citation></ref>
<ref id="B10"><label>10.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Hamamoto</surname><given-names>Y</given-names></name><name><surname>Fujio</surname><given-names>M</given-names></name><name><surname>Nonaka</surname><given-names>M</given-names></name><name><surname>Matsuda</surname><given-names>N</given-names></name><name><surname>Kono</surname><given-names>T</given-names></name><name><surname>Kano</surname><given-names>Y</given-names></name></person-group>. <article-title>Expert consensus on pharmacotherapy for tic disorders in Japan</article-title>. <source>Brain Dev</source>. (<year>2019</year>) <volume>41(6)</volume>:<fpage>501</fpage>&#x2013;<lpage>6</lpage>. <pub-id pub-id-type="doi">10.1016/j.braindev.2019.02.003</pub-id></citation></ref>
<ref id="B11"><label>11.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Pringsheim</surname><given-names>T</given-names></name><name><surname>Okun</surname><given-names>MS</given-names></name><name><surname>Muller-Vahl</surname><given-names>K</given-names></name><name><surname>Martino</surname><given-names>D</given-names></name><name><surname>Jankovic</surname><given-names>J</given-names></name><name><surname>Cavanna</surname><given-names>AE</given-names></name><etal/></person-group> <article-title>Practice guideline recommendations summary: treatment of tics in people with Tourette syndrome and chronic tic disorders</article-title>. <source>Neurology</source>. (<year>2019</year>) <volume>92(19)</volume>:<fpage>896</fpage>&#x2013;<lpage>906</lpage>. <pub-id pub-id-type="doi">10.1212/WNL.0000000000007466</pub-id></citation></ref>
<ref id="B12"><label>12.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wang</surname><given-names>F</given-names></name><name><surname>Ma</surname><given-names>Z</given-names></name><name><surname>Li</surname><given-names>Y</given-names></name><name><surname>Wen</surname><given-names>F</given-names></name><name><surname>Yu</surname><given-names>L</given-names></name><name><surname>Yan</surname><given-names>J</given-names></name><etal/></person-group> <article-title>The clinical intervention choice for pediatric tic disorder patients from a tertiary children&#x2019;s hospital in China: a large-scale retrospective study based on electronic medical records</article-title>. <source>Int Clin Psychopharmacol</source>. (<year>2021</year>) <volume>36</volume>(<issue>4</issue>):<fpage>208</fpage>&#x2013;<lpage>13</lpage>. <pub-id pub-id-type="doi">10.1097/YIC.0000000000000362</pub-id><pub-id pub-id-type="pmid">34030167</pub-id></citation></ref>
<ref id="B13"><label>13.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Yang</surname><given-names>C</given-names></name><name><surname>Yang</surname><given-names>Y</given-names></name><name><surname>Zhang</surname><given-names>L</given-names></name><name><surname>Zhao</surname><given-names>L</given-names></name></person-group>. <article-title>Medication choices in children with tic disorders in Mainland China, Macao, Hong Kong, and Taiwan: perspectives of guardians and physicians</article-title>. <source>Front Pharmacol</source>. (<year>2022</year>) <volume>13</volume>:<fpage>852414</fpage>. <pub-id pub-id-type="doi">10.3389/fphar.2022.852414</pub-id><pub-id pub-id-type="pmid">35592414</pub-id></citation></ref>
<ref id="B14"><label>14.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Liu</surname><given-names>ZS</given-names></name><name><surname>Cui</surname><given-names>YH</given-names></name><name><surname>Sun</surname><given-names>D</given-names></name><name><surname>Lu</surname><given-names>Q</given-names></name><name><surname>Jiang</surname><given-names>YW</given-names></name><name><surname>Jiang</surname><given-names>L</given-names></name><etal/></person-group> <article-title>Current Status, diagnosis, and treatment recommendation for tic disorders in China</article-title>. <source>Front Psychiatry</source>. (<year>2020</year>) <volume>11</volume>:<fpage>774</fpage>. <pub-id pub-id-type="doi">10.3389/fpsyt.2020.00774</pub-id><pub-id pub-id-type="pmid">32903695</pub-id></citation></ref>
<ref id="B15"><label>15.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bitsko</surname><given-names>RH</given-names></name><name><surname>Hutchins</surname><given-names>HJ</given-names></name><name><surname>Whalen</surname><given-names>PL</given-names></name><name><surname>Ogunsola</surname><given-names>H</given-names></name><name><surname>Leeb</surname><given-names>RT</given-names></name><name><surname>Staley</surname><given-names>BS</given-names></name><etal/></person-group> <article-title>Systematic literature review on public health impacts of persistent tic disorders: health care needs and health care use</article-title>. <source>Psychiatr Clin North Am</source>. (<year>2025</year>) <volume>48</volume>(<issue>1</issue>):<fpage>181</fpage>&#x2013;<lpage>201</lpage>. <pub-id pub-id-type="doi">10.1016/j.psc.2024.09.003</pub-id><pub-id pub-id-type="pmid">39880512</pub-id></citation></ref>
<ref id="B16"><label>16.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Wen</surname><given-names>F</given-names></name><name><surname>Gu</surname><given-names>Y</given-names></name><name><surname>Yan</surname><given-names>J</given-names></name><name><surname>Liu</surname><given-names>J</given-names></name><name><surname>Wang</surname><given-names>F</given-names></name><name><surname>Yu</surname><given-names>L</given-names></name><etal/></person-group> <article-title>Revisiting the structure of the Yale Global tic Severity Scale (YGTSS) in a sample of Chinese children with tic disorders</article-title>. <source>BMC Psychiatry</source>. (<year>2021</year>) <volume>21</volume>(<issue>1</issue>):<fpage>394</fpage>. <pub-id pub-id-type="doi">10.1186/s12888-021-03399-5</pub-id><pub-id pub-id-type="pmid">34372795</pub-id></citation></ref>
<ref id="B17"><label>17.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Roessner</surname><given-names>V</given-names></name><name><surname>Eichele</surname><given-names>H</given-names></name><name><surname>Stern</surname><given-names>JS</given-names></name><name><surname>Skov</surname><given-names>L</given-names></name><name><surname>Rizzo</surname><given-names>R</given-names></name><name><surname>Debes</surname><given-names>NM</given-names></name><etal/></person-group> <article-title>European Clinical guidelines for tourette syndrome and other tic disorders-version 2.0. Part III: pharmacological treatment</article-title>. <source>Eur Child Adolesc Psychiatry</source>. (<year>2022</year>) <volume>31</volume>(<issue>3</issue>):<fpage>425</fpage>&#x2013;<lpage>41</lpage>. <pub-id pub-id-type="doi">10.1007/s00787-021-01899-z</pub-id><pub-id pub-id-type="pmid">34757514</pub-id></citation></ref>
<ref id="B18"><label>18.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Nilles</surname><given-names>C</given-names></name><name><surname>Martino</surname><given-names>D</given-names></name><name><surname>Fletcher</surname><given-names>J</given-names></name><name><surname>Pringsheim</surname><given-names>T</given-names></name></person-group>. <article-title>Have we forgotten what tics are? A re-exploration of tic phenomenology in youth with primary tics</article-title>. <source>Mov Disord Clin Pract</source>. (<year>2023</year>) <volume>10</volume>(<issue>5</issue>):<fpage>764</fpage>&#x2013;<lpage>73</lpage>. <pub-id pub-id-type="doi">10.1002/mdc3.13703</pub-id><pub-id pub-id-type="pmid">37205249</pub-id></citation></ref>
<ref id="B19"><label>19.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Desai</surname><given-names>I</given-names></name><name><surname>Kumar</surname><given-names>N</given-names></name><name><surname>Goyal</surname><given-names>V</given-names></name></person-group>. <article-title>An update on the diagnosis and management of tic disorders</article-title>. <source>Ann Indian Acad Neurol</source>. (<year>2023</year>) <volume>26</volume>(<issue>6</issue>):<fpage>858</fpage>&#x2013;<lpage>70</lpage>. <pub-id pub-id-type="doi">10.4103/aian.aian_724_23</pub-id><pub-id pub-id-type="pmid">38229610</pub-id></citation></ref>
<ref id="B20"><label>20.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Groth</surname><given-names>C</given-names></name><name><surname>Mol Debes</surname><given-names>N</given-names></name><name><surname>Rask</surname><given-names>CU</given-names></name><name><surname>Lange</surname><given-names>T</given-names></name><name><surname>Skov</surname><given-names>L</given-names></name></person-group>. <article-title>Course of Tourette syndrome and comorbidities in a large prospective clinical study</article-title>. <source>J Am Acad Child Adolesc Psychiatry</source>. (<year>2017</year>) <volume>56</volume>(<issue>4</issue>):<fpage>304</fpage>&#x2013;<lpage>12</lpage>. <pub-id pub-id-type="doi">10.1016/j.jaac.2017.01.010</pub-id><pub-id pub-id-type="pmid">28335874</pub-id></citation></ref>
<ref id="B21"><label>21.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Choi</surname><given-names>S</given-names></name><name><surname>Lee</surname><given-names>H</given-names></name><name><surname>Song</surname><given-names>DH</given-names></name><name><surname>Cheon</surname><given-names>KA</given-names></name></person-group>. <article-title>Population-based epidemiology of pediatric patients with treated tic disorders from real-world evidence in Korea</article-title>. <source>J Child Adolesc Psychopharmacol</source>. (<year>2019</year>) <volume>29</volume>(<issue>10</issue>):<fpage>764</fpage>&#x2013;<lpage>72</lpage>. <pub-id pub-id-type="doi">10.1089/cap.2019.0050</pub-id><pub-id pub-id-type="pmid">31361509</pub-id></citation></ref>
<ref id="B22"><label>22.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kraft</surname><given-names>JT</given-names></name><name><surname>Dalsgaard</surname><given-names>S</given-names></name><name><surname>Obel</surname><given-names>C</given-names></name><name><surname>Thomsen</surname><given-names>PH</given-names></name><name><surname>Henriksen</surname><given-names>TB</given-names></name><name><surname>Scahill</surname><given-names>L</given-names></name></person-group>. <article-title>Prevalence and clinical correlates of tic disorders in a community sample of school-age children</article-title>. <source>Eur Child Adolesc Psychiatry</source>. (<year>2012</year>) <volume>21</volume>(<issue>1</issue>):<fpage>5</fpage>&#x2013;<lpage>13</lpage>. <pub-id pub-id-type="doi">10.1007/s00787-011-0223-z</pub-id><pub-id pub-id-type="pmid">22038343</pub-id></citation></ref>
<ref id="B23"><label>23.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Mataix-Cols</surname><given-names>D</given-names></name><name><surname>Isomura</surname><given-names>K</given-names></name><name><surname>Brander</surname><given-names>G</given-names></name><name><surname>Brikell</surname><given-names>I</given-names></name><name><surname>Lichtenstein</surname><given-names>P</given-names></name><name><surname>Chang</surname><given-names>Z</given-names></name><etal/></person-group> <article-title>Early-life and family risk factors for tic disorder persistence into adulthood</article-title>. <source>Mov Disord</source>. (<year>2023</year>) <volume>38</volume>(<issue>8</issue>):<fpage>1419</fpage>&#x2013;<lpage>27</lpage>. <pub-id pub-id-type="doi">10.1002/mds.29454</pub-id><pub-id pub-id-type="pmid">37246931</pub-id></citation></ref>
<ref id="B24"><label>24.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Cao</surname><given-names>J</given-names></name><name><surname>Zhao</surname><given-names>Y</given-names></name><name><surname>Shan</surname><given-names>X</given-names></name><name><surname>Wei</surname><given-names>HL</given-names></name><name><surname>Guo</surname><given-names>Y</given-names></name><name><surname>Chen</surname><given-names>L</given-names></name><etal/></person-group> <article-title>Brain functional and effective connectivity based on electroencephalography recordings: a review</article-title>. <source>Hum Brain Mapp</source>. (<year>2022</year>) <volume>43</volume>(<issue>2</issue>):<fpage>860</fpage>&#x2013;<lpage>79</lpage>. <pub-id pub-id-type="doi">10.1002/hbm.25683</pub-id><pub-id pub-id-type="pmid">34668603</pub-id></citation></ref>
<ref id="B25"><label>25.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Siniatchkin</surname><given-names>M</given-names></name><name><surname>Van Bogaert</surname><given-names>P</given-names></name></person-group>. <article-title>Pathophysiology of encephalopathy related to continuous spike and waves during sleep: the contribution of neuroimaging</article-title>. <source>Epileptic Disord</source>. (<year>2019</year>) <volume>21</volume>(<issue>S1</issue>):<fpage>48</fpage>&#x2013;<lpage>53</lpage>. <pub-id pub-id-type="doi">10.1684/epd.2019.1057</pub-id><pub-id pub-id-type="pmid">31149901</pub-id></citation></ref>
<ref id="B26"><label>26.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Cothros</surname><given-names>N</given-names></name><name><surname>Martino</surname><given-names>D</given-names></name><name><surname>McMorris</surname><given-names>C</given-names></name><name><surname>Stewart</surname><given-names>D</given-names></name><name><surname>Tehrani</surname><given-names>A</given-names></name><name><surname>Pringsheim</surname><given-names>T</given-names></name></person-group>. <article-title>Prescriptions for alpha agonists and antipsychotics in children and youth with tic disorders: a pharmacoepidemiologic study</article-title>. <source>Tremor Other Hyperkinet Mov</source>. (<year>2019</year>) <volume>9</volume>:<fpage>15</fpage>. <pub-id pub-id-type="doi">10.7916/tohm.v0.645</pub-id></citation></ref>
<ref id="B27"><label>27.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Farhat</surname><given-names>LC</given-names></name><name><surname>Behling</surname><given-names>E</given-names></name><name><surname>Landeros-Weisenberger</surname><given-names>A</given-names></name><name><surname>Levine</surname><given-names>JLS</given-names></name><name><surname>Macul Ferreira de Barros</surname><given-names>P</given-names></name><name><surname>Wang</surname><given-names>Z</given-names></name><etal/></person-group> <article-title>Comparative efficacy, tolerability, and acceptability of pharmacological interventions for the treatment of children, adolescents, and young adults with tourette&#x2019;s syndrome: a systematic review and network meta-analysis</article-title>. <source>Lancet Child Adolesc Health</source>. (<year>2023</year>) <volume>7</volume>(<issue>2</issue>):<fpage>112</fpage>&#x2013;<lpage>26</lpage>. <pub-id pub-id-type="doi">10.1016/S2352-4642(22)00316-9</pub-id><pub-id pub-id-type="pmid">36528030</pub-id></citation></ref>
<ref id="B28"><label>28.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ricketts</surname><given-names>EJ</given-names></name><name><surname>Woods</surname><given-names>DW</given-names></name><name><surname>Espil</surname><given-names>FM</given-names></name><name><surname>McGuire</surname><given-names>JF</given-names></name><name><surname>Stiede</surname><given-names>JT</given-names></name><name><surname>Schild</surname><given-names>J</given-names></name><etal/></person-group> <article-title>Childhood predictors of long-term tic severity and tic impairment in Tourette&#x2019;s disorder</article-title>. <source>Behav Ther</source>. (<year>2022</year>) <volume>53</volume>(<issue>6</issue>):<fpage>1250</fpage>&#x2013;<lpage>64</lpage>. <pub-id pub-id-type="doi">10.1016/j.beth.2022.07.002</pub-id><pub-id pub-id-type="pmid">36229120</pub-id></citation></ref></ref-list>
</back>
</article>