Effects of non-invasive brain stimulation in the treatment of sleep disorders : a protocol for a systematic review and meta-analysis of randomized controlled trials

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These disturbances, including insomnia and excessive daytime sleepiness, contribute to cognitive decline, mood disorders, and decreased physical health. Non-invasive brain stimulation (NIBS) techniques, including transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), have emerged as potential treatments for various conditions, with growing interest in their application for sleep disorders. While some studies suggest positive effects, the evidence remains inconsistent, with variations in study designs, protocols, and outcomes. Furthermore, existing meta-analyses have not adequately addressed subgroup analyses, which are crucial for identifying more specific treatment parameters and patient characteristics. This systematic review and meta-analysis aim to fill this gap by evaluating the efficacy of NIBS for sleep disturbances, focusing on the quality of evidence, treatment parameters, and potential moderators, ultimately informing clinical practice and guiding future research in this field. Method and analysis: This systematic review and meta-analysis will include randomized controlled trials (RCTs) that compare the effects of NIBS with sham stimulation on sleep disorders. A thorough literature search will be conducted, covering the period from the beginning of each database’s record to January 2025. The following databases will be searched: PubMed, EMBASE, Web of Science (WOS), Physiotherapy Evidence Database (PEDro), and The Chinese National Knowledge Infrastructure (CNKI). Two independent reviewers will evaluate the articles and assess their methodological quality using the Cochrane Risk of Bias tool. Data will be extracted using a standardized template. The meta-analysis will determine the overall effect of NIBS on sleep outcomes, with heterogeneity assessed through I². Subgroup and sensitivity analyses will be performed to investigate treatment variables and the robustness of the results. Ethics and dissemination: This systematic review does not require ethical approval. The results of the study will be shared at scientific conferences and published in journals with peer review. Systematic review registration: PROSPERO registration number CRD42025645170. non-invasive brain stimulation1 sleep disorders2 protocol3 meta-analysis4 Figures Figure 1 Introduction Sleep disorders are a prevalent global health concern affecting a significant portion of the global population, with nearly 30% of adults experiencing sleep disturbances such as insomnia[1–3], in addition to sleep disorders such as obstructive sleep apnea and restless legs syndrome[4,5]. These disorders not only compromise sleep quality but also contribute to the development and exacerbation of various physical and mental health conditions, including cardiovascular disease, depression, and cognitive decline[6,7]. Among them, insomnia and related sleep disturbances have been identified as major contributors to poor quality of life and reduced daily functioning, significantly affecting individuals' ability to perform everyday tasks and maintain social relationships[8,9]. Conventional treatments for sleep disorders primarily involve pharmacological interventions such as sedatives and hypnotics[10,11]. While these medications can be effective in the short term, they often come with significant adverse side effects, such as dependence and tolerance[12–15]. This has led to growing interest in non-pharmacological alternatives for treating sleep disorders. Non-invasive brain stimulation is a promising therapeutic approach for a variety of neurological and psychiatric conditions[16], including sleep disorders[17,18]. NIBS techniques, such as tDCS and repetitive transcranial magnetic stimulation (rTMS)[19,20], have gained attention due to their ability to modulate brain activity without the need for invasive procedures[21]. tDCS delivers low-intensity electrical current to the brain, which can either increase or decrease neuronal excitability depending on the polarity of the stimulation[22,23]. rTMS, in contrast, uses magnetic pulses to induce electrical currents in the brain, leading to changes in cortical excitability[24,25]. Both techniques have been shown to have beneficial effects on cognitive and mood disorders and have demonstrated promise in regulating sleep[26–29]. Sleep is a dynamic neurophysiological process coordinated by neural networks across multiple brain regions. Key mechanisms involve: the suprachiasmatic nucleus (SCN) of the hypothalamus coordinates circadian rhythm regulation; the brainstem reticular formation maintaining arousal via noradrenergic neurons; GABAergic neurons in the basal forebrain initiating sleep through inhibition of arousal systems; while the prefrontal cortex modulates behavioral aspects of sleep-wake regulation[30–32]. Recent research has begun to explore the potential of NIBS to target brain regions involved in sleep regulation, offering a novel approach to improving sleep quality[18,33]. Specifically, both rTMS and tDCS have been used to stimulate regions such as the dorsolateral prefrontal cortex (DLPFC), which plays a key role in regulating sleep[34,35]. While initial studies have shown promising results, the overall efficacy of NIBS in treating sleep disorders is still being researched, with some studies reporting positive outcomes and others yielding inconclusive or conflicting findings[36,37]. A major challenge in evaluating the efficacy of NIBS for sleep disorders is the methodological heterogeneity across studies. Differences in stimulation protocols, such as the frequency, intensity, and duration of stimulation, as well as variations in the targeted brain regions and patient populations (e.g., primary sleep disorders versus those with comorbid conditions), have made it difficult to draw consistent conclusions[38,39]. Additionally, despite the growing interest in NIBS as a treatment for sleep disorders, no systematic review or meta-analysis has specifically focused on synthesizing evidence from RCTs examining the effects of NIBS on sleep outcomes. To fill this gap, we propose conducting a systematic review and meta-analysis of RCTs to evaluate the effectiveness of NIBS for sleep disorders, particularly focusing on the impact of stimulation on different brain regions. The goal of this systematic review and meta-analysis is to provide a comprehensive and rigorous synthesis of the available evidence on NIBS for sleep disorders. By aggregating data from high-quality RCTs, we aim to offer a clearer understanding of the overall effectiveness of NIBS as a non-pharmacological intervention for improving sleep outcomes. This review will also explore potential moderating factors that may influence the efficacy of NIBS, including the stimulation modality, the targeted brain region and patient characteristics. By conducting this analysis, we hope to identify optimal treatment parameters and provide evidence-based recommendations for clinicians who wish to incorporate NIBS into their therapeutic strategies for sleep disorders. The innovative aspect of this study lies in its focus on providing a comprehensive meta-analysis of randomized controlled trials, which allows for the most rigorous assessment of treatment efficacy. By synthesizing data from multiple RCTs, we can achieve a higher level of statistical power, leading to more reliable conclusions regarding the effects of NIBS on sleep. Furthermore, our focus on NIBS interventions targeting specific brain regions offers a unique perspective on how different areas of the brain may play a role in regulating sleep and may provide insights into more personalized treatment approaches. In summary, this systematic review and meta-analysis seeks to address important gaps in the current literature by offering a rigorous, evidence-based evaluation of NIBS for treating sleep disorders. By identifying the most effective stimulation protocols and understanding the mechanisms behind these effects, our study has the potential to advance clinical practice and offer a non-invasive, safe, and effective treatment option for individuals suffering from sleep disorders. Objective In this paper, we report on the protocol of a systematic review and meta-analysis that will: 1. Describe the application of NIBS in the treatment of sleep disorders; 2. Quantitatively assess the effectiveness of NIBS interventions in improving clinical outcomes related to sleep disorders; 3. Examine the heterogeneity in the results of previous studies through subgroup analyses. Methods This protocol will be developed following the guidelines outlined by the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) and has been registered with the International Prospective Register of Systematic Reviews (PROSPERO), under registration number CRD42025645170. Criteria for selecting studies for this review Type of studies The present study will include RCTs that compare a group receiving NIBS treatment for sleep disorders with a control group undergoing sham stimulation. Observational and descriptive study designs, such as cohort studies, case series, case reports, and non-randomized studies, will be excluded. Types of participants This review will encompass studies focusing on individuals diagnosed with various sleep disorders, particularly those experiencing disturbances due to conditions such as traumatic brain injury, chronic insomnia, depression, chronic stress, Parkinson's disease (PD), fibromyalgia, sleep issues in older adults, sleep disorders in people with substance use or drug dependence, and sleep disturbances linked to cancer. Eligible studies will include participants aged 18 or older, with no gender restrictions. Studies will be excluded if they involve participants with contraindications to NIBS. Furthermore, studies in which participants have significant cognitive impairments or other conditions that hinder meaningful participation in the intervention will also be excluded. Search strategy for identification of studies Electronic searches The search will be carried out across five databases: PubMed, EMBASE, Web of Science (WOS), Physiotherapy Evidence Database (PEDro), and China National Knowledge Infrastructure (CNKI). No restrictions will be applied regarding language or publication location. If needed, an independent interpreter will translate articles into English for analysis. Relevant studies will be identified by combining keywords and Medical Subject Headings (MeSH) related to transcranial magnetic stimulation, transcranial direct current stimulation, and sleep disorders. Customized search strategies (supplementary file 1) will be developed for each database to improve the accuracy of the search. Search of other sources A manual search of the reference lists of the included studies will be conducted to identify any potentially relevant studies that were not found through the electronic search. The grey literature will not be included in the search. Types of outcome measures This study aims to investigate the effects of NIBS on sleep disorders by assessing various sleep-related outcomes. The primary outcome will be sleep quality, evaluated using the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Pittsburgh Insomnia Rating Scale (PIRS). Secondary outcomes will include sleep-related parameters such as Polysomnography (PSG), Epworth Sleepiness Scale (ESS), Parkinson's Disease Sleep Scale (PDSS), and Clinical Global Impression Scale (CGI), as well as objective measures such as Total Sleep Time (TST), Sleep Onset Latency (SOL), Wake After Sleep Onset (WASO), Apnea-Hypopnea Index (AHI), Oxygen Desaturation Index (ODI), along with depression and anxiety assessments (HAMD and HAMA). These outcomes will provide a comprehensive understanding of NIBS's potential efficacy in improving both subjective and objective sleep parameters in various patient populations. Data collection and management The study selection will adhere to the PRISMA guidelines (Figure 1). Two reviewers (Y. W. and S. Q.) will conduct a search of databases to identify relevant titles and abstracts. The results will be imported into EndNote 20 citation software, which will automatically remove duplicates, with any remaining duplicates being manually eliminated. Following the inclusion and exclusion criteria, the two independent reviewers (Y. W. and S. Q.) will screen the titles and abstracts to exclude unrelated reports. Full-text analysis will be performed on potentially relevant studies. The entire process will be carried out through consensus, and in case of disagreements, a third reviewer (Q. G.) will act as an arbitrator. If any published data is insufficient for analysis, corresponding authors will be contacted via email to request the original data. Data extraction Following the selection of studies, two reviewers (Y. W. and S. Q.) will extract data independently from each included study. This will encompass details such as authors, country, study design, sample size, participant demographics (age, sex, sleep disorder type, comorbidities), and specifics of NIBS techniques (e.g., TMS, tDCS), along with stimulation parameters and treatment frequency. Additionally, information regarding the intervention and control groups, the number of treatment sessions, and key sleep outcomes (e.g., sleep onset latency, total sleep time) will be documented. Any discrepancies in data extraction will be addressed through cross-checking with the original text, with a third reviewer (Q. G.) involved to resolve any persistent disagreements. Assessment of risk of bias Two reviewers, Y. W. and S. Q., will independently evaluate the potential risk of bias using the Physiotherapy Evidence Database (PEDro) scale[40]. This scale comprises 11 criteria, each assessed as either present or absent. The final score will be derived from 10 of these items, excluding item 1, which addresses external validity. A PEDro score of 11 indicates excellent quality, scores ranging from 8 to 10 represent good quality, scores of 6 or 7 reflect fair quality, and scores of 5 or lower suggest low quality. In case of any discrepancies between the reviewers, they will resolve them through discussion. If they are unable to reach an agreement, a third reviewer, Q. G., will be consulted. When sufficient data is available, the potential for reporting bias will be evaluated using a funnel plot[41]. This plot is a graphical representation that compares the estimated treatment effects (shown on the x-axis) of individual studies against their sample sizes (on the y-axis). In the absence of bias, studies with smaller sample sizes will be distributed at the lower end of the plot, with a denser concentration at the higher end as sample sizes increase. Asymmetry in the funnel plot may signal publication bias and can aid in detecting effects from smaller studies. Quality of evidence The strength of evidence for each outcome will be assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system[42]. This framework examines factors such as bias risk, imprecision, inconsistency, indirectness, and publication bias to determine whether the evidence quality should be downgraded. Conversely, evidence quality may be elevated in situations where a substantial effect size, a dose-response relationship, or potential residual confounders are identified that could influence the observed results. The quality of outcomes will be independently evaluated by two reviewers, Y. W. and S. Q., using the GRADE methodology. Measures of treatment effect For studies with similar outcome measures, data will be combined for meta-analysis. Continuous variables will be reported with the 95% confidence interval (CI) and mean difference (MD), and the significance of the mean effect size will be assessed. A significance level of P < 0.05 will be applied to all statistical tests. The mean effect will be expressed as MD along with its 95% CI. For binary outcomes, the risk ratio (RR) and 95% CI will be computed. Dealing with missing data In the event of missing data, the authors will be reached out to for further details. If they are unable to supply the required information within two months, an intention-to-treat analysis will be conducted using the extrapolated data. The potential impact of this approach will be addressed in the discussion section of the systematic review. Assessment of heterogeneity For our systematic review and meta-analysis on the effects of NIBS in treating sleep disorders, we will use Review Manager (version 5.3) for data analysis, presenting summary statistics via standardized mean difference (SMD) or weighted mean difference (WMD) with 95% confidence intervals (CIs). Due to anticipated clinical and methodological diversity across studies, a random-effects model will be applied to account for heterogeneity, assessed using the I² statistic. An I² value above 50% will indicate substantial heterogeneity, guiding model selection. In case of high heterogeneity or non-comparable outcome data, we will conduct qualitative synthesis. Statistical significance will be set at P < 0.05. Sensitivity analysis To assess the robustness of the findings, we will conduct a sensitivity analysis by excluding studies with poor quality, lack of blinded outcome evaluation, and missing follow-up data. This will help determine the stability of the results. Analysis of subgroups or subsets Following the initial meta-analyses, a subgroup analysis will examine how methodological variations and participant differences affect NIBS outcomes for sleep disorders. Factors such as the type of NIBS technique (e.g., TMS or tDCS), stimulation direction (e.g., facilitatory vs. inhibitory), stimulation target (e.g., L-DLPFC vs. R-DLPFC) and the underlying causes of sleep disorders (e.g., insomnia, obstructive sleep apnea, neurodegenerative conditions) will be considered. This analysis aims to deepen our understanding of how these variables impact NIBS efficacy, providing insights to optimize treatment strategies for individuals with diverse clinical profiles. Strengths and Limitation of this study To our knowledge, this will be the first systematic review and meta-analysis to investigate the effects of NIBS on sleep disorders. This study will provide a rigorous synthesis of RCTs, focusing on the overall impact of NIBS and assessing potential heterogeneity through subgroup and sensitivity analyses. Previous meta-analyses have not adequately addressed subgroup heterogeneity, which has limited their applicability. This protocol seeks to address this gap by conducting an in-depth exploration of treatment parameters and NIBS techniques. One limitation of the study is the restriction to English-language publications. Declarations Patient and public involvement This study will not involve direct participation from patients or the public, as it is a secondary analysis derived from existing research. Ethics and dissemination This review does not require ethical approval. The results of the study will be shared at scientific conferences and published in journals with peer review. All publications and presentations related to the study will undergo authorization and review by the research team. Review status The reviewers have begun exploring relevant studies through electronic databases. This review is anticipated to be finished by December 2025. Author affiliations 1 Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu, People’s Republic of China 2 Key Laboratory of Rehabilitation Medicine in Sichuan Province, West China Hospital, Sichuan University, Chengdu, People’s Republic of China * Corresponding author: Qiang Gao Email address： Shutao Qiu: [email protected] Yixin Wei: [email protected] Kang He: [email protected] Liuxia Wu: [email protected] Yitong Qiu: [email protected] Runting Ma: [email protected] Xiangxiang Zhang: [email protected] Chaoran Gao: [email protected] Qiang Gao: [email protected] Contributors Y. W., S. Q. are joint first authors. Y. W., S. Q., K. H., and L. W. were each involved in the conception, design, writing, and editing of the study protocol. Y. Q., and R. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6139210","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":516861229,"identity":"f5ca3b25-f7a9-4458-ab57-3f7ad5c703da","order_by":0,"name":"Shutao 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1","display":"","copyAsset":false,"role":"figure","size":53649,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of data collection and management\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-6139210/v1/2a2dbbeff0db79ba0de3d322.png"},{"id":109800239,"identity":"2143d6e8-62a9-485b-acc0-b941a3c18bb8","added_by":"auto","created_at":"2026-05-22 15:37:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":197310,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6139210/v1/0f9a5d1a-f5d5-4681-87e3-01a1faf81a07.pdf"},{"id":92445643,"identity":"f84645f4-d1da-4a94-95b6-456a40638d07","added_by":"auto","created_at":"2025-09-29 20:06:18","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":21480,"visible":true,"origin":"","legend":"","description":"","filename":"supplementaryfile1.docx","url":"https://assets-eu.researchsquare.com/files/rs-6139210/v1/d316c4b1f851ad4b1297b8ba.docx"}],"financialInterests":"","formattedTitle":"Effects of non-invasive brain stimulation in the treatment of sleep disorders : a protocol for a systematic review and meta-analysis of randomized controlled trials","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSleep disorders are a prevalent global health concern affecting a significant portion of the global population, with nearly 30% of adults experiencing sleep disturbances such as insomnia[1\u0026ndash;3], in addition to sleep disorders such as obstructive sleep apnea and restless legs syndrome[4,5]. These disorders not only compromise sleep quality but also contribute to the development and exacerbation of various physical and mental health conditions, including cardiovascular disease, depression, and cognitive decline[6,7]. Among them, insomnia and related sleep disturbances have been identified as major contributors to poor quality of life and reduced daily functioning, significantly affecting individuals\u0026apos; ability to perform everyday tasks and maintain social relationships[8,9]. Conventional treatments for sleep disorders primarily involve pharmacological interventions such as sedatives and hypnotics[10,11]. While these medications can be effective in the short term, they often come with significant adverse side effects, such as dependence and tolerance[12\u0026ndash;15]. This has led to growing interest in non-pharmacological alternatives for treating sleep disorders.\u003c/p\u003e\n\u003cp\u003eNon-invasive brain stimulation is a promising therapeutic approach for a variety of neurological and psychiatric conditions[16], including sleep disorders[17,18]. NIBS techniques, such as tDCS and repetitive transcranial magnetic stimulation (rTMS)[19,20], have gained attention due to their ability to modulate brain activity without the need for invasive procedures[21]. tDCS delivers low-intensity electrical current to the brain, which can either increase or decrease neuronal excitability depending on the polarity of the stimulation[22,23]. rTMS, in contrast, uses magnetic pulses to induce electrical currents in the brain, leading to changes in cortical excitability[24,25]. Both techniques have been shown to have beneficial effects on cognitive\u0026nbsp;and mood disorders and have demonstrated promise in regulating sleep[26\u0026ndash;29].\u003c/p\u003e\n\u003cp\u003eSleep is a dynamic neurophysiological process coordinated by neural networks across multiple brain regions. Key mechanisms involve: the suprachiasmatic nucleus (SCN) of the hypothalamus coordinates circadian rhythm regulation; the brainstem reticular formation maintaining arousal via noradrenergic neurons; GABAergic neurons in the basal forebrain initiating sleep through inhibition of arousal systems; while the prefrontal cortex modulates behavioral aspects of sleep-wake regulation[30\u0026ndash;32]. Recent research has begun to explore the potential of NIBS to target brain regions involved in sleep regulation, offering a novel approach to improving sleep quality[18,33]. Specifically, both rTMS and tDCS have been used to stimulate regions such as the dorsolateral prefrontal cortex (DLPFC), which plays a key role in regulating sleep[34,35]. While initial studies have shown promising results, the overall efficacy of NIBS in treating sleep disorders is still being researched, with some studies reporting positive outcomes and others yielding inconclusive or conflicting findings[36,37].\u003c/p\u003e\n\u003cp\u003eA major challenge in evaluating the efficacy of NIBS for sleep disorders is the methodological heterogeneity across studies. Differences in stimulation protocols, such as the frequency, intensity, and duration of stimulation, as well as variations in the targeted brain regions and patient populations (e.g., primary sleep disorders versus those with comorbid conditions), have made it difficult to draw consistent conclusions[38,39]. Additionally, despite the growing interest in NIBS as a treatment for sleep disorders, no systematic review or meta-analysis has specifically focused on synthesizing evidence from RCTs examining the effects of NIBS on sleep outcomes. To fill this gap, we propose conducting a systematic review and meta-analysis of RCTs to evaluate the effectiveness of NIBS for sleep disorders, particularly focusing on the impact of stimulation on different brain regions.\u003c/p\u003e\n\u003cp\u003eThe goal of this systematic review and meta-analysis is to provide a comprehensive and rigorous synthesis of the available evidence on NIBS for sleep disorders. By aggregating data from high-quality RCTs, we aim to offer a clearer understanding of the overall effectiveness of NIBS as a non-pharmacological intervention for improving sleep outcomes. This review will also explore potential moderating factors that may influence the efficacy of NIBS, including the stimulation modality, the targeted brain region and patient characteristics. By conducting this analysis, we hope to identify optimal treatment parameters and provide evidence-based recommendations for clinicians who wish to incorporate NIBS into their therapeutic strategies for sleep disorders.\u003c/p\u003e\n\u003cp\u003eThe innovative aspect of this study lies in its focus on providing a comprehensive meta-analysis of randomized controlled trials, which allows for the most rigorous assessment of treatment efficacy. By synthesizing data from multiple RCTs, we can achieve a higher level of statistical power, leading to more reliable conclusions regarding the effects of NIBS on sleep. Furthermore, our focus on NIBS interventions targeting specific brain regions offers a unique perspective on how different areas of the brain may play a role in regulating sleep and may provide insights into more personalized treatment approaches.\u003c/p\u003e\n\u003cp\u003eIn summary, this systematic review and meta-analysis seeks to address important gaps in the current literature by offering a rigorous, evidence-based evaluation of NIBS for treating sleep disorders. By identifying the most effective stimulation protocols and understanding the mechanisms behind these effects, our study has the potential to advance clinical practice and offer a non-invasive, safe, and effective treatment option for individuals suffering from sleep disorders.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn this paper, we report on the protocol of a systematic review and meta-analysis that will:\u003c/p\u003e\n\u003cp\u003e1. Describe the application of NIBS in the treatment of sleep disorders;\u003c/p\u003e\n\u003cp\u003e2. Quantitatively assess the effectiveness of NIBS interventions in improving clinical outcomes related to sleep disorders;\u003c/p\u003e\n\u003cp\u003e3. Examine the heterogeneity in the results of previous studies through subgroup analyses.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis protocol will be developed following the guidelines outlined by the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) and has been registered with the International Prospective Register of Systematic Reviews (PROSPERO), under registration number CRD42025645170.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCriteria for selecting studies for this review\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eType of studies\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe present study will include RCTs that compare a group receiving NIBS treatment for sleep disorders with a control group undergoing sham stimulation. Observational and descriptive study designs, such as cohort studies, case series, case reports, and non-randomized studies, will be excluded.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eTypes of participants\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis review will encompass studies focusing on individuals diagnosed with various sleep disorders, particularly those experiencing disturbances due to conditions such as traumatic brain injury, chronic insomnia, depression, chronic stress, Parkinson\u0026apos;s disease (PD), fibromyalgia, sleep issues in older adults, sleep disorders in people with substance use or drug dependence, and sleep disturbances linked to cancer. Eligible studies will include participants aged 18 or older, with no gender restrictions.\u003c/p\u003e\n\u003cp\u003eStudies will be excluded if they involve participants with contraindications to NIBS. Furthermore, studies in which participants have significant cognitive impairments or other conditions that hinder meaningful participation in the intervention will also be excluded.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSearch strategy for\u0026nbsp;identification of\u0026nbsp;studies\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eElectronic searches\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe search will be carried out across five databases: PubMed, EMBASE, Web of Science (WOS), Physiotherapy Evidence Database (PEDro), and China National Knowledge Infrastructure (CNKI). No restrictions will be applied regarding language or publication location. If needed, an independent interpreter will translate articles into English for analysis. Relevant studies will be identified by combining keywords and Medical Subject Headings (MeSH) related to transcranial magnetic stimulation, transcranial direct current stimulation, and sleep disorders. Customized search strategies (supplementary file 1) will be developed for each database to improve the accuracy of the search.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSearch of other sources\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA manual search of the reference lists of the included studies will be conducted to identify any potentially relevant studies that were not found through the electronic search. The grey literature will not be included in the search.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eTypes of outcome measures\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study aims to investigate the effects of NIBS on sleep disorders by assessing various sleep-related outcomes. The primary outcome will be sleep quality, evaluated using the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Pittsburgh Insomnia Rating Scale (PIRS). Secondary outcomes will include sleep-related parameters such as Polysomnography (PSG), Epworth Sleepiness Scale (ESS), Parkinson\u0026apos;s Disease Sleep Scale (PDSS), and Clinical Global Impression Scale (CGI), as well as objective measures such as Total Sleep Time (TST), Sleep Onset Latency (SOL), Wake After Sleep Onset (WASO), Apnea-Hypopnea Index (AHI), Oxygen Desaturation Index (ODI), along with depression and anxiety assessments (HAMD and HAMA). These outcomes will provide a comprehensive understanding of NIBS\u0026apos;s potential efficacy in improving both subjective and objective sleep parameters in various patient populations.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData collection and management\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study selection will adhere to the PRISMA guidelines (Figure 1). Two reviewers (Y. W. and S. Q.) will conduct a search of databases to identify relevant titles and abstracts. The results will be imported into EndNote 20 citation software, which will automatically remove duplicates, with any remaining duplicates being manually eliminated. Following the inclusion and exclusion criteria, the two independent reviewers (Y. W. and S. Q.) will screen the titles and abstracts to exclude unrelated reports. Full-text analysis will be performed on potentially relevant studies. The entire process will be carried out through consensus, and in case of disagreements, a third reviewer (Q. G.) will act as an arbitrator. If any published data is insufficient for analysis, corresponding\u0026nbsp;authors will be contacted via email to request the original data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eData extraction\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFollowing the selection of studies, two reviewers (Y. W. and S. Q.) will extract data independently from each included study. This will encompass details such as authors, country, study design, sample size, participant demographics (age, sex, sleep disorder type, comorbidities), and specifics of NIBS techniques (e.g., TMS, tDCS), along with stimulation parameters and treatment frequency. Additionally, information regarding the intervention and control groups, the number of treatment sessions, and key sleep outcomes (e.g., sleep onset latency, total sleep time) will be documented. Any discrepancies in data extraction will be addressed through cross-checking with the original text, with a third reviewer (Q. G.) involved to resolve any persistent disagreements.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eAssessment of risk of bias\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTwo reviewers, Y. W. and S. Q., will independently evaluate the potential risk of bias using the Physiotherapy Evidence Database (PEDro) scale[40]. This scale comprises 11 criteria, each assessed as either present or absent. The final score will be derived from 10 of these items, excluding item 1, which addresses external validity. A PEDro score of 11 indicates excellent quality, scores ranging from 8 to 10 represent good quality, scores of 6 or 7 reflect fair quality, and scores of 5 or lower suggest low quality. In case of any discrepancies between the reviewers, they will resolve them through discussion. If they are unable to reach an agreement, a third reviewer, Q. G., will be consulted.\u003c/p\u003e\n\u003cp\u003eWhen sufficient data is available, the potential for reporting bias will be evaluated using a funnel plot[41]. This plot is a graphical representation that compares the estimated treatment effects (shown on the x-axis) of individual studies against their sample sizes (on the y-axis). In the absence of bias, studies with smaller sample sizes will be distributed at the lower end of the plot, with a denser concentration at the higher end as sample sizes increase. Asymmetry in the funnel plot may signal publication bias and can aid in detecting effects from smaller studies.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eQuality of evidence\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe strength of evidence for each outcome will be assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system[42]. This framework examines factors such as bias risk, imprecision, inconsistency, indirectness, and publication bias to determine whether the evidence quality should be downgraded. Conversely, evidence quality may be elevated in situations where a substantial effect size, a dose-response relationship, or potential residual confounders are identified that could influence the observed results. The quality of outcomes will be independently evaluated by two reviewers, Y. W. and S. Q., using the GRADE methodology.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eMeasures of treatment effect\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFor studies with similar outcome measures, data will be combined for meta-analysis. Continuous variables will be reported with the 95% confidence interval (CI) and mean difference (MD), and the significance of the mean effect size will be assessed. A significance level of P \u0026lt; 0.05 will be applied to all statistical tests. The mean effect will be expressed as MD along with its 95% CI. For binary outcomes, the risk ratio (RR) and 95% CI will be computed.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eDealing with missing data\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the event of missing data, the authors will be reached out to for further details. If they are unable to supply the required information within two months, an intention-to-treat analysis will be conducted using the extrapolated data. The potential impact of this approach will be addressed in the discussion section of the systematic review.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eAssessment of heterogeneity\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFor our systematic review and meta-analysis on the effects of NIBS in treating sleep disorders, we will use Review Manager (version 5.3) for data analysis, presenting summary statistics via standardized mean difference (SMD) or weighted mean difference (WMD) with 95% confidence intervals (CIs). Due to anticipated clinical and methodological diversity across studies, a random-effects model will be applied to account for heterogeneity, assessed using the I\u0026sup2; statistic. An I\u0026sup2; value above 50% will indicate substantial heterogeneity, guiding model selection. In case of high heterogeneity or non-comparable outcome data, we will conduct qualitative synthesis. Statistical significance will be set at P \u0026lt; 0.05.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSensitivity analysis\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo assess the robustness of the findings, we will conduct a sensitivity analysis by excluding studies with poor quality, lack of blinded outcome evaluation, and missing follow-up data. This will help determine the stability of the results.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eAnalysis of subgroups or subsets\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFollowing the initial meta-analyses, a subgroup analysis will examine how methodological variations and participant differences affect NIBS outcomes for sleep disorders. Factors such as the type of NIBS technique (e.g., TMS or tDCS), stimulation direction (e.g., facilitatory vs. inhibitory), stimulation target (e.g., L-DLPFC vs. R-DLPFC) and the underlying causes of sleep disorders (e.g., insomnia, obstructive sleep apnea, neurodegenerative conditions) will be considered. This analysis aims to deepen our understanding of how these variables impact NIBS efficacy, providing insights to optimize treatment strategies for\u0026nbsp;individuals with diverse clinical profiles.\u003c/p\u003e\n"},{"header":"Strengths and Limitation of this study ","content":"\u003cp\u003eTo our knowledge, this will be the first systematic review and meta-analysis to investigate the effects of NIBS on sleep disorders. This study will provide a rigorous synthesis of RCTs, focusing on the overall impact of NIBS and assessing potential heterogeneity through subgroup and sensitivity analyses. Previous meta-analyses have not adequately addressed subgroup heterogeneity, which has limited their applicability. This protocol seeks to address this gap by conducting an in-depth exploration of treatment parameters and NIBS techniques. One limitation of the study is the restriction to English-language publications.\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003ePatient and public involvement\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study will not involve direct participation from patients or the public, as it is a secondary analysis derived from existing research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics and dissemination\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis review does not require ethical approval. The results of the study will be shared at scientific conferences and published in journals with peer review. All publications and presentations related to the study will undergo authorization and review by the research team.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eReview status\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe reviewers have begun exploring relevant studies through electronic databases. This review is anticipated to be finished by December 2025.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eAuthor affiliations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e1\u003c/sup\u003eDepartment of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu, People\u0026rsquo;s Republic of China\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e2\u003c/sup\u003eKey Laboratory of Rehabilitation Medicine in Sichuan Province, West China Hospital, Sichuan University, Chengdu, People\u0026rsquo;s Republic of China\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e*\u003c/sup\u003eCorresponding author: Qiang Gao\u003c/p\u003e\n\u003cp\u003eEmail address：\u003c/p\u003e\n\u003cp\u003eShutao Qiu: [email protected]\u003c/p\u003e\n\u003cp\u003eYixin Wei: [email protected]\u003c/p\u003e\n\u003cp\u003eKang He: [email protected]\u003c/p\u003e\n\u003cp\u003eLiuxia Wu: [email protected]\u003c/p\u003e\n\u003cp\u003eYitong Qiu: [email protected]\u003c/p\u003e\n\u003cp\u003eRunting Ma: [email protected]\u003c/p\u003e\n\u003cp\u003eXiangxiang Zhang: [email protected]\u003c/p\u003e\n\u003cp\u003eChaoran Gao: [email protected]\u003c/p\u003e\n\u003cp\u003eQiang Gao: [email protected]\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eContributors\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eY. W., S. Q. are joint first authors. Y. W., S. Q., K. H., and L. W. were each involved in the conception, design, writing, and editing of the study protocol. Y. Q., and R. M. contributed to the critical revision of the manuscript for important intellectual content and approved the final version of the manuscript. All authors have read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e This study is funded by the NSFC 82372562 from the National Natural Science Foundation of China.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u003c/strong\u003e All authors affirm that they have received no funding or support from any organization for the work submitted. They also declare that, in the past three years, they have had no financial connections with any entity that could have a vested interest in the submitted work. Additionally, they confirm there are no other relationships or activities that could be perceived as influencing the content of the submitted work.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eSutton EL. Insomnia. Ann Intern Med. 2021;174:ITC33\u0026ndash;48. \u003c/li\u003e\n\u003cli\u003eMorin CM, Jarrin DC. Epidemiology of Insomnia: Prevalence, Course, Risk Factors, and Public Health Burden. Sleep Med Clin. 2022;17:173\u0026ndash;91. \u003c/li\u003e\n\u003cli\u003eAbraham O, Pu J, Schleiden LJ, Albert SM. Factors contributing to poor satisfaction with sleep and healthcare seeking behavior in older adults. Sleep Health. 2017;3:43\u0026ndash;8. \u003c/li\u003e\n\u003cli\u003eK Pavlova M, Latreille V. Sleep Disorders. Am J Med. 2019;132:292\u0026ndash;9. \u003c/li\u003e\n\u003cli\u003eDopheide JA. Insomnia overview: epidemiology, pathophysiology, diagnosis and monitoring, and nonpharmacologic therapy. Am J Manag Care. 2020;26:S76\u0026ndash;84. \u003c/li\u003e\n\u003cli\u003eKhan MT, Franco RA. Complex sleep apnea syndrome. Sleep Disord. 2014;2014:798487. \u003c/li\u003e\n\u003cli\u003eLi Y, Que M, Wang X, Zhan G, Zhou Z, Luo X, et al. Exploring Astrocyte-Mediated Mechanisms in Sleep Disorders and Comorbidity. Biomedicines. 2023;11:2476. \u003c/li\u003e\n\u003cli\u003eRiemann D, Nissen C, Palagini L, Otte A, Perlis ML, Spiegelhalder K. The neurobiology, investigation, and treatment of chronic insomnia. Lancet Neurol. 2015;14:547\u0026ndash;58. \u003c/li\u003e\n\u003cli\u003eMedalie L, Cifu AS. Management of Chronic Insomnia Disorder in Adults. JAMA. 2017;317:762\u0026ndash;3. \u003c/li\u003e\n\u003cli\u003eMadari S, Golebiowski R, Mansukhani MP, Kolla BP. Pharmacological Management of Insomnia. Neurotherapeutics. 2021;18:44\u0026ndash;52. \u003c/li\u003e\n\u003cli\u003eRiemann D, Baglioni C, Bassetti C, Bjorvatn B, Dolenc Groselj L, Ellis JG, et al. European guideline for the diagnosis and treatment of insomnia. J Sleep Res. 2017;26:675\u0026ndash;700. \u003c/li\u003e\n\u003cli\u003eAhmed QA. Effects of common medications used for sleep disorders. Crit Care Clin. 2008;24:493\u0026ndash;515, vi. \u003c/li\u003e\n\u003cli\u003eWinkler A, Auer C, Doering BK, Rief W. Drug treatment of primary insomnia: a meta-analysis of polysomnographic randomized controlled trials. CNS Drugs. 2014;28:799\u0026ndash;816. \u003c/li\u003e\n\u003cli\u003eFlaxer JM, Heyer A, Francois D. Evidenced-Based Review and Evaluation of Clinical Significance: Nonpharmacological and Pharmacological Treatment of Insomnia in the Elderly. Am J Geriatr Psychiatry. 2021;29:585\u0026ndash;603. \u003c/li\u003e\n\u003cli\u003eMorin CM, Inoue Y, Kushida C, Poyares D, Winkelman J, Guidelines Committee Members, et al. Endorsement of European guideline for the diagnosis and treatment of insomnia by the World Sleep Society. Sleep Med. 2021;81:124\u0026ndash;6. \u003c/li\u003e\n\u003cli\u003ePark EJ, Lee SJ, Koh DY, Han YM. Repetitive transcranial magnetic stimulation to treat depression and insomnia with chronic low back pain. Korean J Pain. 2014;27:285\u0026ndash;9. \u003c/li\u003e\n\u003cli\u003eHerrero Babiloni A, Bellemare A, Beetz G, Vinet S-A, Martel MO, Lavigne GJ, et al. The effects of non-invasive brain stimulation on sleep disturbances among different neurological and neuropsychiatric conditions: A systematic review. Sleep Med Rev. 2021;55:101381. \u003c/li\u003e\n\u003cli\u003eLanza G, Fisicaro F, Cantone M, Pennisi M, Cosentino FII, Lanuzza B, et al. Repetitive transcranial magnetic stimulation in primary sleep disorders. Sleep Med Rev. 2023;67:101735. \u003c/li\u003e\n\u003cli\u003eKrishnan C, Santos L, Peterson MD, Ehinger M. Safety of noninvasive brain stimulation in children and adolescents. Brain Stimul. 2015;8:76\u0026ndash;87. \u003c/li\u003e\n\u003cli\u003eKesikburun S. Non-invasive brain stimulation in rehabilitation. Turk J Phys Med Rehabil. 2022;68:1\u0026ndash;8. \u003c/li\u003e\n\u003cli\u003eFerrucci R, Priori A. Noninvasive stimulation. Handb Clin Neurol. 2018;155:393\u0026ndash;405. \u003c/li\u003e\n\u003cli\u003eBrunoni AR, Nitsche MA, Bolognini N, Bikson M, Wagner T, Merabet L, et al. Clinical research with transcranial direct current stimulation (tDCS): challenges and future directions. Brain Stimul. 2012;5:175\u0026ndash;95. \u003c/li\u003e\n\u003cli\u003eChan MMY, Yau SSY, Han YMY. The neurobiology of prefrontal transcranial direct current stimulation (tDCS) in promoting brain plasticity: A systematic review and meta-analyses of human and rodent studies. Neurosci Biobehav Rev. 2021;125:392\u0026ndash;416. \u003c/li\u003e\n\u003cli\u003eQian F-F, He Y-H, Du X-H, Lu H-X, He R-H, Fan J-Z. Repetitive transcranial magnetic stimulation promotes neurological functional recovery in rats with traumatic brain injury by upregulating synaptic plasticity-related proteins. Neural Regen Res. 2023;18:368\u0026ndash;74. \u003c/li\u003e\n\u003cli\u003eIglesias AH. Transcranial Magnetic Stimulation as Treatment in Multiple Neurologic Conditions. Curr Neurol Neurosci Rep. 2020;20:1. \u003c/li\u003e\n\u003cli\u003eBegemann MJ, Brand BA, Ćurčić-Blake B, Aleman A, Sommer IE. Efficacy of non-invasive brain stimulation on cognitive functioning in brain disorders: a meta-analysis. Psychol Med. 2020;50:2465\u0026ndash;86. \u003c/li\u003e\n\u003cli\u003eLanza G, Cantone M, Aric\u0026ograve; D, Lanuzza B, Cosentino FII, Paci D, et al. Clinical and electrophysiological impact of repetitive low-frequency transcranial magnetic stimulation on the sensory-motor network in patients with restless legs syndrome. Ther Adv Neurol Disord. 2018;11:1756286418759973. \u003c/li\u003e\n\u003cli\u003eS\u0026aacute;nchez-Escand\u0026oacute;n O, Arana-Lechuga Y, Ter\u0026aacute;n-P\u0026eacute;rez G, Ruiz-Chow A, Gonz\u0026aacute;lez-Robles R, Shkurovich-Bialik P, et al. Effect of low-frequency repetitive transcranial magnetic stimulation on sleep pattern and quality of life in patients with focal epilepsy. Sleep Med. 2016;20:37\u0026ndash;40. \u003c/li\u003e\n\u003cli\u003eBhattacharya A, Mrudula K, Sreepada SS, Sathyaprabha TN, Pal PK, Chen R, et al. An Overview of Noninvasive Brain Stimulation: Basic Principles and Clinical Applications. Can J Neurol Sci. 2022;49:479\u0026ndash;92. \u003c/li\u003e\n\u003cli\u003eBaranwal N, Yu PK, Siegel NS. Sleep physiology, pathophysiology, and sleep hygiene. Prog Cardiovasc Dis. 2023;77:59\u0026ndash;69. \u003c/li\u003e\n\u003cli\u003eNahum LH. PHYSIOLOGY OF SLEEP. Conn Med. 1964;28:245\u0026ndash;6. \u003c/li\u003e\n\u003cli\u003eEdgar DM, Dement WC, Fuller CA. Effect of SCN lesions on sleep in squirrel monkeys: evidence for opponent processes in sleep-wake regulation. J Neurosci. 1993;13:1065\u0026ndash;79. \u003c/li\u003e\n\u003cli\u003eZhou Q, Liu Z, Yu C, Wang Q, Zhuang W, Tang Y, et al. Effect of combined treatment with transcranial direct current stimulation and repetitive transcranial magnetic stimulation compared to monotherapy for the treatment of chronic insomnia: a randomised, double-blind, parallel-group, controlled trial. BMC Med. 2024;22:538. \u003c/li\u003e\n\u003cli\u003eForogh B, Rafiei M, Arbabi A, Motamed MR, Madani SP, Sajadi S. Repeated sessions of transcranial direct current stimulation evaluation on fatigue and daytime sleepiness in Parkinson\u0026rsquo;s disease. Neurol Sci. 2017;38:249\u0026ndash;54. \u003c/li\u003e\n\u003cli\u003eGuo Y, Zhao X, Zhang X, Li M, Liu X, Lu L, et al. Effects on resting-state EEG phase-amplitude coupling in insomnia disorder patients following 1 Hz left dorsolateral prefrontal cortex rTMS. Hum Brain Mapp. 2023;44:3084\u0026ndash;93. \u003c/li\u003e\n\u003cli\u003eHong JK, Yoon I-Y. Efficacy of cranial electrotherapy stimulation on mood and sense of well-being in people with subclinical insomnia. J Sleep Res. 2024;33:e13978. \u003c/li\u003e\n\u003cli\u003eNardone R, Sebastianelli L, Versace V, Brigo F, Golaszewski S, Pucks-Faes E, et al. Effects of repetitive transcranial magnetic stimulation in subjects with sleep disorders. Sleep Med. 2020;71:113\u0026ndash;21. \u003c/li\u003e\n\u003cli\u003eZhu X, Tabarak S, Que J, Yan W, Lin X, Liu X, et al. Efficiency and safety of continuous theta burst stimulation for primary insomnia: A randomized clinical trial. Sleep Med. 2024;124:77\u0026ndash;83. \u003c/li\u003e\n\u003cli\u003eZhang X, Zhuang S, Wu J, Wang L, Mao C, Chen J, et al. Effects of repetitive transcranial magnetic stimulation over right dorsolateral prefrontal cortex on excessive daytime sleepiness in patients with Parkinson\u0026rsquo;s disease. Sleep Med. 2022;100:133\u0026ndash;8. \u003c/li\u003e\n\u003cli\u003eCashin AG, McAuley JH. Clinimetrics: Physiotherapy Evidence Database (PEDro) Scale. J Physiother. 2020;66:59. \u003c/li\u003e\n\u003cli\u003eSterne JAC, Sutton AJ, Ioannidis JPA, Terrin N, Jones DR, Lau J, et al. Recommendations for examining and interpreting funnel plot asymmetry in meta-analyses of randomised controlled trials. BMJ. 2011;343:d4002. \u003c/li\u003e\n\u003cli\u003eGuyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P, et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ. 2008;336:924\u0026ndash;6. \u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"non-invasive brain stimulation1, sleep disorders2, protocol3, meta-analysis4","lastPublishedDoi":"10.21203/rs.3.rs-6139210/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6139210/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eIntroduction:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSleep disorders are prevalent conditions that significantly impact health and quality of life, often linked to underlying issues such as neurological and psychiatric disorders, chronic pain, and aging. These disturbances, including insomnia and excessive daytime sleepiness, contribute to cognitive decline, mood disorders, and decreased physical health. Non-invasive brain stimulation (NIBS) techniques, including transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), have emerged as potential treatments for various conditions, with growing interest in their application for sleep disorders.\u003c/p\u003e\n\u003cp\u003eWhile some studies suggest positive effects, the evidence remains inconsistent, with variations in study designs, protocols, and outcomes. Furthermore, existing meta-analyses have not adequately addressed subgroup analyses, which are crucial for identifying more specific treatment parameters and patient characteristics. This systematic review and meta-analysis aim to fill this gap by evaluating the efficacy of NIBS for sleep disturbances, focusing on the quality of evidence, treatment parameters, and potential moderators, ultimately informing clinical practice and guiding future research in this field.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethod and analysis:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis systematic review and meta-analysis will include randomized controlled trials (RCTs) that compare the effects of NIBS with sham stimulation on sleep disorders. A thorough literature search will be conducted, covering the period from the beginning of each database’s record to January 2025. The following databases will be searched: PubMed, EMBASE, Web of Science (WOS), Physiotherapy Evidence Database (PEDro), and The Chinese National Knowledge Infrastructure (CNKI). Two independent reviewers will evaluate the articles and assess their methodological quality using the Cochrane Risk of Bias tool. Data will be extracted using a standardized template. The meta-analysis will determine the overall effect of NIBS on sleep outcomes, with heterogeneity assessed through I². Subgroup and sensitivity analyses will be performed to investigate treatment variables and the robustness of the results.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics and dissemination:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis systematic review does not require ethical approval. The results of the study will be shared at scientific conferences and published in journals with peer review.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSystematic review registration:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePROSPERO registration number CRD42025645170.\u003c/p\u003e","manuscriptTitle":"Effects of non-invasive brain stimulation in the treatment of sleep disorders : a protocol for a systematic review and meta-analysis of randomized controlled trials","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-29 19:58:13","doi":"10.21203/rs.3.rs-6139210/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8a7e8c3f-1d3e-4d4f-92eb-38a66f4e8145","owner":[],"postedDate":"September 29th, 2025","published":true,"recentEditorialEvents":[{"type":"decision","content":"Reject before peer review","date":"2026-05-21T22:26:17+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-05-22T02:26:39+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-29 19:58:13","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6139210","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6139210","identity":"rs-6139210","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}