Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics

Copyright © The Author(s). All Rights Reserved. © 2025 GLOBAL PUBLICATION HOUSE | GPH - International Journal of Computer Science and Engineering (GPH-IJCSE) | Open Access under CC BY 4.0 License Mapping Lean Six Sigma Research: Advancing Sustainability through Bibliometrics By: Jacques S. Osmeña ORCID: 0009-0009-3431-8539 Affiliation: Industrial Engineering Department, College of Technology and Engineering, Palompon Institute of Technology, Palompon, Leyte, Philippines. Abstract Purpose: This paper examines the global evolution of Lean Six Sigma research and its role in advancing sustainable practices. Maps the intellectual structure, thematic trends, and collaborative networks, highlighting its alignment with the United Nations Sustainable Development Goals. Design/methodology/approach: A bibliometric analysis is conducted using Scopus database, covering 2,148 peer-reviewed publications up to 2025. Performance indicators and science mapping techniques, including co-authorship, co-occurrence, and overlay visualizations, are applied through Bibliometrix and VOSviewer to identify influential scholars, institutions, countries, and thematic clusters. Findings: United States, India, and United Kingdom emerge as leading contributors, with Jiju Antony as the most prolific scholar. Thematic clusters are identified: one emphasizing industrial efficiency, sustainability, and digital transformation, and another focused on organizational management, service quality, and healthcare. Trends indicate a shift from traditional process standardization toward integration with Industry 4.0, big data analytics, and sustainability-driven practices. Practical implications: LSS acts as a strategic enabler of operational excellence and sustainable development, guiding practitioners in manufacturing, healthcare, and services. Social implications: LSS supports SDG 9, SDG 12, and SDG 3 by enhancing efficiency, resilience, and quality of life. Originality/value: This is the first comprehensive bibliometric mapping of LSS and sustainability, offering a foundation for global cross-sectoral applications. Keywords: Lean Six Sigma, bibliometric analysis, sustainability, Industry 4.0, healthcare quality, global collaboration, thematic evolution. How to cite: Osmeña, J. (2025). Mapping Lean Six Sigma Research: Advancing Sustainability through Bibliometrics. GPH-International Journal of Computer Science and Engineering, 8(2), 0118. https://doi.org/10.5281/zenodo.17312903 e-ISSN 3050-9661 ARTICLE ID: #02114 10.5281/ZENODO.17312903 VOL. 08 ISSUE 02 JULY-DEC. 2025 Page 01 of 18 Osmeña, J. (2025). Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics. GPH-International Journal of Computer Science and Engineering, 8(2), 01-18. https://doi.org/10.5281/zenodo.17312903 (GPH-IJCSE) | Vol. 8, Issue 02, (July-Dec. 2025) | © Global Publication House | Open Access | www.gphjournal.org Plain Language Summary Lean Six Sigma (LSS) is a widely used approach that helps organizations improve efficiency, reduce waste, and enhance quality. Originally designed for manufacturing, it is now applied in many fields, including healthcare, education, logistics, and government services. Despite its popularity, there has been limited understanding of how research on LSS has developed worldwide over time. This study analyzed more than 2,000 research articles from the Scopus database to map the growth and direction of LSS research. By using bibliometric methods, the study identified the countries, institutions, and authors that contributed most to the field, as well as the major themes and emerging topics. The findings showed that the United States, India, and the United Kingdom were the main leaders in research output, supported by strong international collaboration. Traditional topics like quality management and process control remained important, while new themes such as sustainability, healthcare improvement, and digital transformation became increasingly prominent. These results provide valuable insights for both researchers and practitioners. They highlight how LSS continues to evolve as a global framework that supports operational excellence, sustainability, and innovation across industries and societies. (3335 words) Introduction Lean Six Sigma (LSS) became a cornerstone methodology for enhancing quality, operational efficiency, and organizational excellence across diverse industries. Originally rooted in manufacturing, LSS integrated Lean principles, which emphasized waste elimination, with Six Sigma, which focused on defect reduction, to deliver measurable performance improvements. Over the past two decades, its application expanded into healthcare, education, logistics, public services, and government, underscoring its adaptability and the growing global demand for structured, data-driven strategies that advanced both operational excellence and sustainability (Sony and Naik, 2020). The academic development of LSS mirrored its industrial expansion. Research output increased substantially, particularly in the United States, India, and the United Kingdom, where scholars such as Jiju Antony shaped discourse on critical success factors, organizational readiness, and cross-sectoral applications (Antony et al., 2020). Institutions such as Heriot-Watt University and the Mayo Clinic emerged as leading hubs of both theoretical advancement and applied research, especially in healthcare quality improvement. Thematic studies demonstrated continuity in core topics—total quality management, lean production, and Six Sigma while highlighting a shift toward agile practices, Industry 4.0 integration, and human-centered improvement (Tortorella et al., 2021). Keyword analyses further emphasized sustainability and service contexts, where human factors were increasingly central (Donthu et al., 2021). Despite these advances, comprehensive global bibliometric perspectives that integrated productivity, thematic evolution, and collaboration 02 Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics GPH-International Journal of Computer Science and Engineering (GPH-IJCSE) | © 2025 Global Publication House | Open Access | remained limited. This study addressed that gap by mapping the intellectual structure of LSS, identifying leading contributors and thematic developments, and examining its alignment with sustainable practices. Prior reviews of sustainable LSS frameworks underscored the fragmented state of current knowledge (Formigoni Carvalho Walter et al., 2021). More recently, this transition was described as Lean Six Sigma 4.0, reflecting its adaptation to digital transformation challenges (Citybabu and Yamini, 2023). Methods This study adopted a bibliometric analysis to systematically examine the global evolution of Lean Six Sigma (LSS) research and its intersections with sustainable quality practices. Bibliometric analysis was a well-established quantitative method that enabled researchers to map the intellectual, thematic, and collaborative structures of a field through the statistical evaluation of publication and citation data (Donthu et al., 2021). By combining performance analysis and science mapping techniques, the approach not only identified prolific authors, institutions, and countries but also revealed thematic clusters, keyword trends, and the temporal progression of research topics. The dataset was extracted from the Scopus database on August 8, 2025, yielding 2,148 results. Scopus was selected for its comprehensive indexing of peer-reviewed literature in management, engineering, and applied sciences. The search strategy targeted publications related to Lean Six Sigma and associated quality improvement methodologies, without restrictions on sector or geographic location, thereby ensuring a broad representation of scholarly contributions. This bibliometric design allowed for both descriptive and relational insights, aligning with the study’s aim to provide a global, longitudinal, and thematic overview of LSS research. By situating the findings within broader industrial and societal contexts, the analysis not only quantified research activity but also uncovered evolving priorities and collaborative patterns that shaped the field’s trajectory. Data analysis was conducted using a combination of R’s Bibliometrix package and VOSviewer software. Bibliometrix generated statistical summaries such as annual scientific production, author productivity, and citation impact, while VOSviewer facilitated network visualizations, including co-authorship maps, keyword co-occurrence networks, thematic evolution overlays, and strategic diagrams. These visual tools enabled the interpretation of complex relationships among research actors, themes, and time periods in an accessible manner. 03 Osmeña, J. (2025). Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics. GPH-International Journal of Computer Science and Engineering, 8(2), 01-18. https://doi.org/10.5281/zenodo.17312903 (GPH-IJCSE) | Vol. 8, Issue 02, (July-Dec. 2025) | © Global Publication House | Open Access | www.gphjournal.org Figure 1. Methodological framework of the study The study employed a rigorous four-phase analytical process to map the quality improvement research landscape (Figure 1). First, comprehensive data were retrieved from Scopus, and bibliographic records were systematically collected to ensure a representative dataset. Second, the dataset underwent meticulous pre-processing, where metadata were normalized and standardized to guarantee analytical consistency. Third, performance analysis was conducted to identify field leaders, spotlighting the most influential authors, institutions, countries, and publications shaping quality improvement discourse. Finally, advanced science mapping techniques were applied to visualize the field’s intellectual structure, revealing evolving collaboration networks, thematic clusters, and temporal trends. Collectively, these stages told the story of the development of quality research. This multi-stage approach enabled the study to move beyond simple bibliometric counts and to generate meaningful insights into the field’s past, present, and future directions. Results The global distribution of Lean Six Sigma (LSS) research (Figure 2) demonstrated a landscape that was geographically diverse yet quantitatively imbalanced. The United States (1,515 documents) and India (1,115 documents) dominated scholarly output, reflecting their strong academic infrastructures, industrial demand for process improvement, and longstanding engagement with quality management frameworks. The United Kingdom (535), Brazil (295), Italy (284), and Ireland (249) followed as significant contributors within their regional contexts. Additional notable contributions came from China, the Netherlands, Malaysia, and the United Arab Emirates, underscoring the methodology’s expanding relevance across continents. This distribution mirrored broader economic and developmental patterns. Mature economies leveraged LSS to advance high-value manufacturing, service-sector innovation, and healthcare process optimization, while emerging and developing nations increasingly adopted LSS as a strategic tool for enhancing operational efficiency, global competitiveness, and 04 Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics GPH-International Journal of Computer Science and Engineering (GPH-IJCSE) | © 2025 Global Publication House | Open Access | sustainable growth. These patterns highlighted both the global appeal of LSS and the unequal capacity for research production, shaped by differences in funding, industrial adoption rates, and policy priorities. Figure 2. Geographical distribution of respondents across the globe The bibliometric performance analysis (Table 1) identified Jiju Antony (University of Northumbria, UK) as the most prolific and influential scholar in LSS research, with 147 publications representing 35% of the total output of the top authors garnering more than 6,800 citations and an h-index of 49. He was closely followed by Rajeev Rathi (India) and Jose Arturo Garza-Reyes (UK), each with over 40 publications and high citation averages, particularly in extending LSS into areas such as supply chain sustainability and service-sector quality. Other prominent contributors, including Olivia McDermott (Ireland), Michael Sony (UK), and Ronald Does (Netherlands), advanced LSS applications in healthcare quality, cultural readiness, and statistical rigor. Scholars such as Mahender Singh Kaswan, Vikas Swarankar, Shreeranga Bhat, Elizabeth Cudney, and Mahipal P. Singh enriched the intellectual diversity of the field by contributing valuable regional perspectives from Asia, Europe, and North America. Additionally, Vijaya M. Sunder (India) stood out for his high citation-per-publication ratio (55.05), reflecting significant influence despite a relatively smaller number of publications. 05 Osmeña, J. (2025). Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics. GPH-International Journal of Computer Science and Engineering, 8(2), 01-18. https://doi.org/10.5281/zenodo.17312903 (GPH-IJCSE) | Vol. 8, Issue 02, (July-Dec. 2025) | © Global Publication House | Open Access | www.gphjournal.org Table I. The list of top 10 authors of lean six sigma research AUTHOR’S NAME AFFILIATION TP (%) TC ACP H-INDEX RANK Antony, Jiju University of Northumbria (United Kingdom) 147 (34%) 6,881 46.8 49 1st Rathi, Rajeev National Institute of Technology (India) 41 (9%) 1,714 41.8 22 2nd GarzaReyes, Jose Arturo University of Derby (United Kingdom) 40 (9%) 1,743 43.6 20 3rd McDermott, Olivia University of Galway (Ireland) 35 (8%) 578 16.5 12 4th Sony, Micheal Oxford Brookes Business School (United Kingdom) 30 (7%) 592 19.7 13 5th Does, Ronald J.M.M. Universiteit van Amsterdam (Netherlands) 27 (6%) 1,112 41.9 15 6th Kaswan, Mahender Singh Lovely Professional University (India) 22 (5%) 902 41 14 7th Swarnakar, Vikas Khalifa University of Science and Technology (United Arab Emirates) 21 (5%) 512 24.4 12 8th Bhat, Shreeranga St Joseph Engineering College (India) 20 (5%) 607 30.6 11 9th Cudney, Elizabeth A. Missouri University of Science and Technology (United States) 20 (5%) 590 29.5 13 9th Singh, Mahipal P. Lovely Professional University (India) 20 (5%) 749 37.5 12 9th Sunder M, Vijaya M.. Indian School of Business (India) 19 (4%) 1046 55.1 15 10th *Abbreviations: ACP, average citations per paper: TC, total citations; TP, total publication, Rank was based on TP. 06 Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics GPH-International Journal of Computer Science and Engineering (GPH-IJCSE) | © 2025 Global Publication House | Open Access | The institutional performance analysis (Table 2) revealed that the University of Northumbria led global LSS research output, contributing 147 publications 35% of the total from the top institutions supported by more than 6,800 citations and an h-index of 49. The Institute of Technology in India and the University of Derby in the United Kingdom followed with 41 and 40 publications, respectively, both maintaining strong citation averages. Other notable contributors included the University of Galway (Ireland) and Oxford Brookes Business School (UK), each advancing LSS applications across diverse sectors. Additional institutions such as the Universiteit van Amsterdam (Netherlands), Lovely Professional University (India), Khalifa University of Science and Technology (UAE), St. Joseph Engineering College (India), and the University of Science and Technology (USA) further demonstrated the geographically distributed nature of LSS research. India’s National Institutes of Technology at Kurukshetra and Tiruchirappalli, while producing fewer publications compared to leading institutions, contributed valuable regional insights and domain-specific expertise to the field. Table II. The top 10 institutions of lean six sigma research AFFILIATION/INSTITUTION COIUNTRY TP (%) TC ACP H-INDEX RANK Heriot-Watt University United Kingdom 71 (16%) 3,398 47.9 36 1st Khalifa University of Science and Technology United Arab Emirates 49 (11%) 1,004 20.5 21 2nd University of Galway Ireland 44 (10%) 774 17.6 16 3rd Lovely Professional University India 43 (9%) 1,728 40.2 22 4th University of Derby United Kingdom 41 (9%) 1,793 43.7 21 5th Universiteit van Amsterdam Netherlands 37 (8%) 892 24.1 17 6th University of Northumbria United Kingdom 34 (8%) 482 14.2 11 7th Universitá degli Studi di Napoli Federico II Italy 24 (5%) 885 36.9 14 8th 07 Osmeña, J. (2025). Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics. GPH-International Journal of Computer Science and Engineering, 8(2), 01-18. https://doi.org/10.5281/zenodo.17312903 (GPH-IJCSE) | Vol. 8, Issue 02, (July-Dec. 2025) | © Global Publication House | Open Access | www.gphjournal.org University of Strathclyde United Kingdom 24 (5%) 2,187 91.1 22 8th Universidade Federal de São Carlos Brazil 23 (5%) 584 25.4 11 9th National Institute of Technology Kurukshetra India 21 (5%) 72 3.4 5 10th University College Dublin Ireland 21 (5%) 350 16.7 13 10th National Institute of Technology Tiruchirappalli India 21 (5%) 79 3.8 6 10th AFFILIATION/INSTITUTION COIUNTRY TP (%) TC ACP H-INDEX RANK *Abbreviations: ACP, average citations per paper: TC, total citations; TP, total publication, Rank was based on TP. The three-field plot (Figure 3) illustrated the interconnectedness of the LSS research landscape by linking the most cited references (CR) on the left, the key contributing authors (AU) in the center, and the main themes or keywords (KW_Merged) on the right. Foundational works such as Banawi and Abdulaziz’s framework for improving construction processes and study on critical failure factors stood out as cornerstones that continued to influence the field. At the center of the network were prolific scholars including Jiju Antony, Rajeev Rathi, Olivia McDermott, Jose Arturo Garza-Reyes, and Michael Sony, whose research shaped both the methodological foundations and practical applications of LSS. On the right, recurring keywords such as lean six sigma, six sigma, lean production, and process improvement reflected the field’s core priorities, while terms such as human, quality improvement, and efficiency pointed to evolving areas of interest. 08 Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics GPH-International Journal of Computer Science and Engineering (GPH-IJCSE) | © 2025 Global Publication House | Open Access | Figure 3. Relationships between cited references, authors, and research keywords The trend topics analysis (Figure 4) captured the thematic evolution of Lean Six Sigma (LSS) research over the past two decades and revealed a clear trajectory from traditional operational priorities toward more technologically advanced and socially responsive themes. In the mid2000s, the discourse was dominated by practical efficiency drivers such as inventory control and industrial management, reflecting LSS’s strong manufacturing roots and its early role in streamlining production processes. Over time, the thematic focus progressively expanded to incorporate forward-looking priorities such as sustainability, Industry 4.0, machine learning, and quality of service, signaling the integration of LSS with digital transformation and broader organizational performance goals. Particularly notable was the recent surge in terms such as human, health services, and sustainable development, which pointed to an increasing recognition of the human-centric and societal dimensions of process improvement. This thematic shift illustrated how LSS evolved beyond a narrow industrial efficiency framework into a versatile, cross-sector approach that addressed technological advancement, environmental responsibility, and public service quality, aligning closely with contemporary global priorities. 09 Osmeña, J. (2025). Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics. GPH-International Journal of Computer Science and Engineering, 8(2), 01-18. https://doi.org/10.5281/zenodo.17312903 (GPH-IJCSE) | Vol. 8, Issue 02, (July-Dec. 2025) | © Global Publication House | Open Access | www.gphjournal.org methodologies, big data analytics, and patient-centered healthcare. Healthcare emerged as a particularly critical domain, where LSS reduced errors and costs while improving outcomes, thereby demonstrating societal as well as industrial value. In the industrial domain, casebased studies reinforced the value of structured frameworks. For instance, a DMAIC-based LSS framework significantly improved efficiency and product quality in the Indian automotive industry, underscoring the role of context-specific approaches in sustaining operational gains (Teli et al., 2021). Emerging priorities such as machine learning, pandemic resilience, and sustainable operations positioned LSS as more than a process-improvement tool. It served as a strategic enabler of innovation, societal resilience, and sustainable development (Nadeem et al., 2023; Kurnia and Purba, 2021). These shifts also highlighted opportunities for cross-integration of Lean and Industry 4.0 practices (Alsadi et al., 2023). By integrating methodological foundations with sector-specific applications, LSS continued to evolve as a globally relevant framework for addressing both industrial challenges and societal needs. Conclusion Guided by its objective to map the intellectual structure, key contributors, and thematic evolution of Lean Six Sigma (LSS), this bibliometric analysis confirmed that LSS had developed into a globally significant framework bridging industrial efficiency with service quality, healthcare innovation, and sustainability focused practices. The results demonstrated how leading scholars, diverse institutions, and strong international collaborations shaped the field, enabling the transfer of knowledge across regions and sectors. Over time, LSS research progressed from foundational process improvement to the integration of advanced technologies, data analytics, and human centered approaches that addressed complex societal and industrial needs. This thematic convergence directly supported several United Nations Sustainable Development Goals, most notably SDG 9, SDG 12, and SDG 3, by promoting innovation, resource efficiency, and improved health outcomes. By delivering a comprehensive overview of the field’s trajectory and emerging priorities, this study provided a strategic foundation for future research aimed at leveraging LSS as a catalyst for both operational excellence and sustainable development in an interconnected global economy. The dominance of the United Kingdom, India, and the United States reflected a fusion of mature innovation systems and rapid capability development, while the scholarly output of top authors accelerated the refinement and global dissemination of best practices. The rising prominence of healthcare applications highlighted LSS’s adaptability to high impact sectors, where operational efficiency translated into both economic savings and lives saved. Similarly, the emphasis on certifications signaled a strategic move toward global standardization, ensuring that LSS principles remained relevant and transferable across industries and borders. Collectively, these elements positioned LSS not merely as a process improvement methodology but as a globally adaptable framework capable of driving sustainable industrial growth, enhancing service quality, and fostering international collaboration, aligning closely with the imperatives of a dynamic, interconnected world economy. 16 Mapping Lean Six Sigma Research: Advancing Sustainability Through Bibliometrics GPH-International Journal of Computer Science and Engineering (GPH-IJCSE) | © 2025 Global Publication House | Open Access | Article Information and Declarations Funding: None Declared Acknowledgements: None Declared Conflict of Interest: None Declared Supplementary material: None Declared Data Access Statement: The bibliometric data were retrieved from the Scopus database on August 8, 2025, yielding 2,148 records. Due to database licensing restrictions, the full dataset cannot be shared, but the search strategy is available from the corresponding author upon request. 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