1. Introduction

Nocturnal enuresis, commonly known as bedwetting, represents a significant health concern affecting approximately 5–10% of children worldwide, with prevalence decreasing with age ^1,2. This condition, defined as involuntary urination during sleep in children over five years of age, poses considerable challenges for affected children and their families, impacting psychological well-being, social development, and quality of life ^3,4.

The etiology of nocturnal enuresis is multifactorial, involving genetic predisposition, delayed maturation of central nervous system pathways controlling bladder function, nocturnal polyuria, reduced functional bladder capacity, and arousal difficulties ⁵. The International Children’s Continence Society (ICCS) classifies nocturnal enuresis as either monosymptomatic (without daytime symptoms) or non-monosymptomatic (with daytime symptoms), and as primary (never having achieved dryness) or secondary (recurrence after at least six months of dryness) ⁶.

Management approaches for nocturnal enuresis have evolved significantly over the past four decades, reflecting an enhanced understanding of its pathophysiology ⁷. Current evidence-based treatment options include behavioral interventions such as enuresis alarms, pharmacological interventions primarily involving desmopressin, and complementary approaches ¹. The standardization of terminology, assessment protocols, and treatment algorithms by organizations such as the ICCS has significantly contributed to improved clinical care and research quality ⁸.

While numerous studies have examined the etiology, clinical characteristics, and treatment efficacy of nocturnal enuresis, a comprehensive bibliometric analysis of the global research landscape in this field has not been previously conducted. Bibliometric analysis offers valuable insights into publication patterns, influential authors and institutions, international collaborations, and evolving research trends ⁹.

The objective of this study was to perform a bibliometric assessment of the global literature on nocturnal enuresis. Publication patterns, collaborative authorship, country-level contributions, and thematic evolution were examined to characterize the current research landscape and to identify areas that may warrant further investigation.

2. Methodology

2.1. Data source and search strategy

This study was designed as a bibliometric analysis to map the scientific output related to nocturnal enuresis over an extended time period. Bibliographic records were retrieved exclusively from the Web of Science (WoS) Core Collection, which is widely recognized for its standardized indexing structure and suitability for citation-based analyses. The WoS database indexes a broad range of scholarly publications spanning multiple disciplines and is widely regarded as a reliable source for bibliometric research ^10,11. In addition, the WoS database provides long-term archival coverage, with indexed records dating back to the early 20th century ¹².

The literature search approach applied in this study is described as follows: ALL = (“nocturnal enuresis” OR “enuresis” OR “bedwetting” OR “bed wetting” OR “monosymptomatic nocturnal enuresis” OR “primary nocturnal enuresis” OR “secondary nocturnal enuresis”) AND (“non-pharmacological” OR “non-medical” OR “conservative treatment” OR “behavioral therapy” OR “behavioural therapy” OR “enuresis alarm” OR “bedwetting alarm” OR “conditioning therapy” OR “urotherapy” OR “bladder training” OR “voiding education” OR “timed voiding” OR “motivational therapy” OR “reward system” OR “psychotherapy” OR “hypnotherapy” OR “biofeedback” OR “acupuncture” OR “pelvic floor training” OR “fluid management” OR “dietary modification” ) AND (“child” OR “children” OR “pediatric”).

The literature search was conducted using a predefined search query focusing on pediatric nocturnal enuresis and its clinical management, covering publications from 1980 to 2025. Only peer-reviewed articles written in English were included. Document types such as meeting abstracts, editorials, letters, and conference proceedings were excluded to ensure methodological consistency and reliability of data.

2.2. Eligibility criteria

A predefined set of eligibility criteria was applied to guide study selection. Publications eligible for inclusion consisted of original research articles and review papers published in peer-reviewed journals in English. Items such as conference proceedings, meeting abstracts, editorials, book chapters, letters, early-access articles, corrections, and retracted papers were systematically excluded. A flow diagram summarizing the literature selection process is presented in Figure 1.

Figure 1. Flowchart of the study

2.3. Bibliometric analysis and visualization

Bibliometric analysis was developed over the course of the 20th century and was formally established as a distinct research field in 1969¹³. Since then, bibliometric methods have become widely applied for the systematic evaluation of scientific publications ¹⁴. A quantitative analytical framework was employed to examine published studies within a specific academic field ¹⁵. During the analysis, bibliographic information such as authorship, keywords, journals, countries, publication sources, and cited references was systematically extracted. In addition, co-citation analysis—a method in which two publications are jointly cited by subsequent articles—was applied to explore relationships within the literature. This approach facilitates a more integrative interpretation of the data by revealing underlying intellectual linkages among studies ¹⁶.

The visualization analyses were conducted using the following software tools: VOSviewer (version 1.6.20, Leiden University’s Centre for Science and Technology Studies, Netherlands) ⁹ and R software (version 4.4.2, The R Foundation, New Zealand), which includes the Bibliometrix R package and the Biblioshiny tool (https://bibliometrix.org/home/).¹⁷ VOSviewer, a bibliometric visualization tool developed at Leiden University, Netherlands, applies standardized mapping techniques to generate network visualizations of keywords, institutional collaborations, co-authorship patterns, and related bibliographic entities. The software provides multiple visualization formats, including network, overlay, and density views, enabling clear representation of relationships and thematic structures within the data ⁹. Within the network maps, clusters are represented by different colors, each reflecting patterns of collaboration or thematic association among related entities. The relative size of each node indicates its weight in the network, based on metrics such as the number of publications, references, or keyword occurrences.

The Bibliometrix R package, available within the R software environment, was used alongside the Biblioshiny tool for conducting bibliometric analysis and visualization. This approach assists researchers in comprehending prevailing research trends, focal areas of inquiry, and academic impact within a specific field ¹⁷. All visualizations were generated using raw data extracted from WoS Core Collection; normalization was not applied unless otherwise stated. For the development of the country collaboration network, the full counting method was employed. Under this method, each publication involving authors from multiple countries is assigned a full weight of one to each participating country, ensuring that every international contribution is equally represented in the collaboration strength analysis ¹⁸. Citation impact was assessed using total citation counts; time-normalized metrics such as citations per year were not applied¹⁹.

2.4. Statistical analysis

Annual publication trends were assessed using simple linear regression analysis, with publication year as the independent variable and the number of publications as the dependent variable. Statistical significance was set at p < 0.05. These analyses were performed using IBM SPSS Statistics software (Version 26.0; IBM Corp, United States of America [USA]). No additional normalization was applied to bibliometric data unless explicitly stated.

3. Results

3.1. Database indexes and general distribution

A total of 405 articles were identified in the WoS database. The publication trend analysis of nocturnal enuresis research from 1980 to 2025 exhibited a significant increase over time (Figure 2). The linear regression analysis demonstrated a strong positive correlation between publication year and the number of publications (R² = 0.76, p < 0.001). While the 1980s and early 1990s showed a relatively stable publication pattern with approximately 1–3 articles per year, there was a notable increase starting from 2000 (n = 10). The highest number of publications was observed in 2022 (n = 30), followed by 2024 (n = 26) and 2017 (n = 24). This upward trend in publication frequency indicates growing scientific interest and research activity in the field of nocturnal enuresis over the past four decades, with particularly accelerated growth in the last two decades.

Figure 2. Number of publications on nocturnal enuresis research from 1980 to 2025.

The distribution of these articles across WoS indexes is presented in Table S1. A total of 307 publications were original articles, whereas 98 publications were reviews. The majority of the studies were indexed in the Science Citation Index Expanded (n = 318, 69.3%).

The top 10 publishers are shown in Table S2. Elsevier ranks first with 112 articles, followed by Wiley (n = 55), Springer Nature (n = 41), Lippincott Williams & Wilkins (n = 35), and Taylor & Francis (n = 26). These five publishers constitute approximately 63% of the total publications. As shown in Table S3, among the top funding agencies, the United States Department of Health Human Services supported eight publications.

3.2. Author productivity and collaboration networks

The top 10 authors with the most publications are presented in Table 1. Trygve Nevéus is the most productive author with 13 articles, followed by Alexander von Gontard (n = 11) and Patrina H. Y. Caldwell (n = 8). Author collaboration network analysis (Figure 3) revealed distinct clusters in the research field. The cluster centered on Trygve Nevéus has a wide collaboration network with Malin Borgström, Søren Rittig, Ann Raes, Konstantinos Kamperis, and Cecilie Siggaard Jørgensen. The second largest cluster led by Alexander von Gontard shows strong connections with Catharina Wagner and Justine Niemczyk.

Figure 3. Author collaboration network in nocturnal enuresis research. Each node represents an author, and node size is proportional to the number of publications. Links between nodes indicate co-authorship, with link thickness reflecting collaboration strength based on the number of shared publications. Distinct colors represent collaboration clusters identified using a clustering algorithm. Image created by the authors.

3.3. Country-based publication and citation distribution

As shown in Table 1, among the top 10 countries with the most publications, the USA ranks first with 79 articles and 1,746 citations, followed by Turkey (articles = 38) and the People’s Republic of China (articles = 27). In terms of citation counts, Sweden had the highest citation count (1,092), followed by Belgium (988) and England (879). Country collaboration network analysis (Figure 4) highlights the central role of the USA and the intensive collaboration between European countries.

Figure 4. International collaboration network in nocturnal enuresis research by country. Each node represents a country, with node size corresponding to publication output. Links indicate co-authored publications between countries, and link thickness reflects collaboration strength calculated using the full counting method. Colors represent clusters of countries with stronger collaborative relationships. Image created by the authors.

3.4. Institution-based contributions

The top 10 institutions with the most publications are presented in Table S4. Uppsala University ranks first with 16 articles and 719 citations, followed by Ghent University Hospital (articles = 14, citations = 736), University of Sydney (articles = 12, citations = 272), the Children’s Hospital Westmead (articles = 11, citations = 268), and Aarhus University Hospital (articles = 8, citations = 479). The institutional citation network is shown in Figure 5.

Figure 5. Institutional collaboration network in nocturnal enuresis research. Nodes represent institutions and are scaled according to the number of published articles. Edges indicate institutional co-authorship, with thicker links representing more frequent collaborations. Colors denote clusters of closely collaborating institutions. Image created by the authors.

3.5. Journal distribution and publication sources

The top 10 journals with the most publications are presented in Table 1. The Journal of Pediatric Urology has the highest number of publications, with 52 articles and 884 citations, while the Journal of Urology has the highest number of citations, with 27 articles and 1,134 citations. Scandinavian Journal of Urology and Nephrology (articles = 15, citations = 545), Urology (articles = 15, citations = 226), and Neurouology and Urodynamics (articles = 11, citations = 114) are other important journals. Journal co-citation network analysis (Figure S1) reveals that the Journal of Urology and the Journal of Pediatric Urology are central to the field.

3.6. Keyword analysis and thematic trends

Table S5 presents the top 10 most frequently used keywords. “Enuresis” (n = 91) and “nocturnal enuresis” (n = 87) are the most frequently used keywords, followed by “children” (n = 57), “desmopressin” (n = 42), and “urinary incontinence” (n = 34). The keyword co-occurrence network is shown in Figure 6.

Figure 6. Keyword co-occurrence network in nocturnal enuresis research. Each node represents a keyword, and node size is proportional to its frequency of occurrence. Links indicate co-occurrence within the same publications, with link thickness reflecting the strength of co-occurrence. Distinct colors represent thematic clusters, highlighting the principal research topics in the field. Image created by the authors.

3.7. Text-based network analysis

The text-based network analysis (Figure 7) revealed three main conceptual clusters in the studies. The blue cluster is characterized by terms such as “night,” “week,” “day,” “alarm,” “enuresis alarm,” “desmopressin,” “control group,” and “significant difference,” and particularly reflects clinical efficacy studies related to nocturnal enuresis treatments with alarm and desmopressin, generally focusing on treatment duration and treatment response.

The green cluster—characterized by terms such as “review,” “literature,” “article,” “evidence,” “quality,” “intervention,” “family,” “acupuncture,” and “management”— represents a more holistic body of literature discussing different treatment options, levels of evidence, and application approaches, including systematic reviews and general management strategies with a family dimension.

The red cluster concentrates around terms such as “urinary incontinence,” “incontinence,” “dysfunctional voiding,” “constipation,” “biofeedback,” “anticholinergic,” “urotherapy,” “symptom,” “improvement,” “mean age,” “boy,” and “girl,” covering clinical studies on lower urinary tract dysfunctions, daytime incontinence, constipation, and multi-component treatment programs directed at these conditions. The dense connections between clusters, especially through bridge concepts—such as “management,” “case,” “desmopressin,” and “significant difference”—indicate that the literature on enuresis, urinary incontinence, and general management approach is tightly integrated.

The overlay analysis (Figure 8) reveals not only the content of concepts but also their temporal focus over time. Accordingly, terms such as “night,” “day,” “week,” “enuresis alarm,” “alarm,” “boy,” and “girl” in the upper and upper-right portions of the network, appearing in darker or purple tones, indicate that research initially concentrated around nocturnal enuresis, alarm therapy, and basic demographic variables. Terms such as “desmopressin,” “control group,” “significant difference,” “improvement,” “symptom,” “urotherapy,” and “incontinence” located in the center and regions shifting toward yellow tones suggest that more complex clinical trials—including drug therapy, clinical efficacy, and urotherapy—became prominent in the subsequent period.

Terms such as “urinary incontinence,” “dysfunctional voiding,” “constipation,” “biofeedback,” “anticholinergic,” “management,” “review,” “evidence,” and “quality” in the lower and lower-right parts, with increasingly lighter green–yellow tones, indicate that interest in recent years has shifted to lower urinary tract dysfunctions, accompanying constipation, multi-component treatment programs (e.g., biofeedback, anticholinergic drugs, urotherapy), and review or guideline-like studies evaluating their level of evidence. Overall, the network reveals that the field has evolved over time from simple enuresis- and alarm-focused clinical practices to more comprehensive, evidence-based management models that address functional disorders together.

Figure 7. Thematic map illustrating the conceptual structure of nocturnal enuresis research. Themes are positioned according to centrality (relevance to the field) and density (degree of internal development). Motor themes are located in the upper-right quadrant, whereas emerging or declining themes are located in the lower-left quadrant. Image created by the authors.

Figure 8. Thematic evolution map illustrating changes in research themes over time. Nodes represent thematic clusters, with node size proportional to the number of associated publications. Connecting lines indicate thematic continuity or evolution across time periods, demonstrating shifts in research focus over. Image created by the authors.

3.8. Most cited articles                                                 

Table 2 presents the top 10 most cited articles. The most highly cited article is the standardization document “Evaluation of and Treatment for Monosymptomatic Enuresis” prepared by the ICCS and published in the Journal of Urology (DOI: 10.1016/j.juro.2009.10.043). The second most cited article is a more recent standardization document prepared by the same organization (DOI: 10.1016/j.jpurol.2019.12.020).

4. Discussion

This bibliometric study provides an overview of the worldwide research landscape on nocturnal enuresis, highlighting major publication trends, collaborative patterns, and evolving thematic areas over the last four decades. Our findings demonstrate a significant and steady increase in research output from 1980 to 2025, particularly accelerating after 2000, which reflects growing scientific interest in this condition affecting millions of children worldwide.

The substantial increase in publication volume, as evidenced by the strong positive correlation between year and publication count, aligns with similar growth trends observed in other pediatric urology and pediatric continence research areas ²⁷. This growth coincides with several key developments in the field, including the establishment of standardized terminology and management guidelines by the ICCS ^6,8, increased recognition of the psychosocial impact of enuresis ²⁸, and advances in understanding the pathophysiological mechanisms underlying the condition ²⁹.

Our analysis identified several prolific authors, with Trygve Nevéus and Alexander von Gontard emerging as the most productive contributors with 13 and 11 publications, respectively. These authors have significantly shaped contemporary understanding of nocturnal enuresis through their work on pathophysiology, psychological comorbidities, and treatment approaches ^3,29. The author collaboration network revealed distinct research clusters, primarily centered around Scandinavian, European, and Australian research groups, highlighting the importance of international collaboration in advancing knowledge in this field.

       The country-based analysis revealed the USA as the leading contributor in terms of publication volume (n = 79), while Turkey ranked second (n = 38), representing an emerging focus on enuresis research in the region. This finding is particularly interesting, as it differs from general publication patterns in medical research where traditionally Western European countries and Japan typically follow the USA in research output ³⁰. The strong citation impact of Swedish and Belgian publications (1,092 and 988 citations, respectively), despite lower publication counts, highlights the influential nature of research from these countries, which has primarily focused on pathophysiological mechanisms and optimizing treatment approaches ³¹.

The institutional analysis revealed that Uppsala University and Ghent University Hospital were the most productive institutions, which aligns with the leading role of Scandinavian and European research centers in this field. The prominent position of the University of Sydney and Children’s Hospital Westmead reflects Australia’s significant contribution to evidence-based management approaches for nocturnal enuresis, particularly through their work on alarm interventions and behavioral strategies ⁷.

Journal analysis indicated that the Journal of Pediatric Urology published the highest number of articles (n = 52), while the Journal of Urology garnered the most citations (n = 1,134). This distribution reflects the multidisciplinary nature of enuresis research, spanning urology, pediatrics, and nephrology specialties. The influential role of the Journal of Urology can be partially attributed to its publication of key standardization documents from the ICCS, which have become fundamental reference points in the field ⁸.

Keyword analysis revealed “enuresis” and “nocturnal enuresis” as the most frequently used terms, followed by “children,” “desmopressin,” and “urinary incontinence.” This pattern reflects the core focus of the literature on pediatric populations and primary treatment modalities. The temporal analysis of keyword usage demonstrates an evolution in research focus over time, with early studies (1980s–1990s) concentrating on basic clinical aspects and alarm therapy, transitioning to pharmacological interventions (particularly desmopressin) in the late 1990s and 2000s, and more recently (2010s–2020s) expanding to encompass broader lower urinary tract dysfunctions, associated conditions like constipation, and comprehensive management approaches including urotherapy and biofeedback.

Text-based network analysis identified three distinct conceptual clusters in the literature: (i) clinical efficacy studies related to alarm and desmopressin treatments, (ii) comprehensive literature reviews and evidence evaluation, and (iii) studies on lower urinary tract dysfunctions and multi-component treatment programs. This clustering highlights the progression of the field from single-intervention studies to more holistic approaches that recognize the complex interrelationships between various functional elimination disorders and the need for multimodal management strategies ^3,5.

The most cited articles were primarily standardization documents from the ICCS, underscoring the critical importance of establishing consistent terminology, diagnostic criteria, and treatment approaches in advancing clinical care and research quality. These highly influential papers have facilitated improved communication among researchers and clinicians and enabled more comparable research outcomes across studies ^1,6.

Our findings should be interpreted in light of certain limitations. First, our analysis was restricted to publications indexed in the WoS Core Collection, which is a well-established and widely used database for bibliometric studies. However, this approach may have resulted in the exclusion of relevant publications indexed exclusively in other major databases such as Scopus, PubMed/MEDLINE, or regional databases. Thus, some research outputs, particularly those published in local journals or non-English-language sources, may be underrepresented. Consequently, the findings should be interpreted as reflecting trends within WoS-indexed literature rather than the entirety of global nocturnal enuresis research. Second, citation metrics may be influenced by factors beyond scientific merit, including self-citation, citation networks, and varying citation practices across disciplines. Third, our analysis primarily focused on quantitative metrics and may not fully capture the qualitative impact or clinical relevance of individual contributions. The inclusion of treatment-oriented keywords in our search string may have introduced a selection bias, potentially leading to an underrepresentation of basic science research, molecular mechanisms, and large-scale epidemiological studies that do not explicitly focus on interventional outcomes.

Consequently, our findings should be interpreted primarily as a reflection of the clinical management and therapeutic aspects of nocturnal enuresis rather than its entire biological and sociological spectrum ³¹. In addition, citation counts were analyzed in absolute terms and were not normalized for publication year (e.g., citations per year). As a result, older publications may appear more influential due to longer citation windows. While this approach is common in descriptive bibliometric analyses, future studies incorporating time-normalized citation metrics may allow for more refined comparative interpretations.

Importantly, our findings highlight a notable scarcity of studies addressing the molecular and biological mechanisms underlying nocturnal enuresis. Although the condition is increasingly recognized as multifactorial—encompassing neurodevelopmental, hormonal, and functional components—relatively few investigations have applied modern molecular approaches ³². Emerging genetic studies suggest potential associations with genomic regions involved in circadian regulation, vasopressin signaling, and sleep–arousal pathways, while preliminary metabolomic and proteomic studies have indicated differences in urinary biomarkers and water-handling mechanisms between affected and unaffected children ^34,35. Nevertheless, such studies remain limited in both number and scope.

Future research would benefit from integrating genomic, transcriptomic, proteomic, and metabolomic methodologies with well-characterized clinical phenotypes. Multicenter and longitudinal studies may be particularly valuable in elucidating biological pathways, identifying predictive biomarkers, and supporting the development of personalized management strategies. In parallel, continued investigation into long-term treatment outcomes, persistent enuresis in adolescents and adults, and the role of digital health technologies may further enhance the clinical management of nocturnal enuresis.

5. Conclusion

This bibliometric analysis provides an overview of publication patterns, collaborative structures, and thematic trends in nocturnal enuresis research over the past four decades. The findings suggest a gradual increase in research activity and an evolving focus from descriptive clinical studies toward more comprehensive and multidisciplinary management approaches. As a secondary analysis based on existing literature, the results should be interpreted descriptively rather than as evidence of causal or clinical effectiveness. Nevertheless, the identified patterns may help contextualize current research directions and highlight areas that appear underexplored. Future studies, particularly prospective clinical and translational research, are warranted to further advance understanding and improve management strategies for nocturnal enuresis.