Bibliometric Analysis of Highly Cited Documents on COVID-19 Based on the Web of Science Database

Document Type : Research Paper

Authors

1 Associate Professor, Department of Knowledge and Information Science, University of Tabriz, Tabriz, Iran, (Corresponding author).

2 Professor, Department of Knowledge and Information Science, Uni-versity of Tabriz, Tabriz, Iran.

3 M.A., Department of Knowledge and Information Science, University of Tabriz, Tabriz, Iran.

Abstract

Purpose: The aim of bibliometric analysis is to provide an innovative perspective for advancing scientific research within a specific field. This study seeks to conduct a multidimensional analysis of the characteristics of highly cited documents on COVID-19, using data indexed in the Web of Science from 2013 to 2022.
Methodology: This applied study employs a documentary approach utilizing bibliometric methods. The sample comprised 11,512 highly cited documents related to COVID-19, indexed in the Web of Science database between 2013 and 2022. Data analysis was conducted using Excel, HistCite, ISI.exe, and VOSviewer software.
Findings: The publication of highly cited documents in the field of COVID-19 initially followed an upward trend, peaking in 2020 and 2021, before declining after 2021. Among academic institutions, Huazhong University of Science and Technology led the rankings, receiving 7,122 local citations and 129,224 global citations, with an average of 532 citations per document, earning the title of the most influential university in the COVID-19 domain. Influential research in this field has been dominated by advanced countries such as the United States, China, and the United Kingdom. These three countries have played a pivotal role in advancing COVID-19-related knowledge by contributing more than 50% of the documents. Original articles accounted for the largest share of highly cited COVID-19 documents, with 9,465 documents (82.2%), which received 80,352 local citations and 1,785,024 global citations. Review articles followed with 1,946 documents (16.9%), garnering 10,513 local citations and 368,254 global citations. Among the top 20 most influential journals, The New England Journal of Medicine, The Lancet, and Nature ranked first, receiving 115,840, 95,567, and 79,207 global citations, respectively, as well as 8,455, 7,041, and 6,798 local citations, respectively. Accordingly, The New England Journal of Medicine was recognized as the most influential journal in the COVID-19 field due to its highest number of global citations. In general, 40% of journals with impact factors ranging from 6 to 100 have published 66.5% of the highly cited documents. Out of 1,987 journal titles, 1,110 titles (55.86%) are in the first quartile, collectively publishing 8,726 documents (75.80% of all highly cited documents). In fact, 95% of the highly cited COVID-19 documents were published in journals within the first and second quartiles. The results indicate that the highly cited documents have an average length of 12.11 pages, with titles averaging 14 words; 73% of the document titles fall within a range of 12 ± 5 words. Of the 11,512 highly cited documents, 6,818 (59.23%) were funded. Among these funded documents, the largest share (2,130 documents, or 18.50%) was supported by a single funding source only, with an average of 2.8 funding sources per document. Additional findings revealed that the majority of highly cited documents were published in the field of medical sciences and related disciplines, comprising 9,482 documents (57.55%). This was followed by basic sciences with 3,338 documents (20.26%) and humanities with 2,502 documents (15.18%). Furthermore, engineering accounted for 668 documents (4.05%), and social sciences accounted for 487 documents (2.96%). Other results showed that 20 funding agencies supported 5,726 documents, representing approximately 84% of the funded documents. The National Institutes of Health (NIH) ranked first, funding 1,950 documents (28.60%), followed by the National Natural Science Foundation of China (NSFC) with 818 documents (12%), and the National Institute for Health Research (NIHR) with 502 documents (7.36%). Among the top 20 funding sources, the highest number of documents were supported by agencies from the United States (2,369 documents, 34.75%), China (1,305 documents, 19.15%), and the United Kingdom (1,236 documents, 18.12%). Together, these three countries supported 72% of the highly cited COVID-19 documents.
Conclusion: A comprehensive analysis of highly cited COVID-19 publications provides valuable insights for the academic community, including researchers, students, and authors. The study highlights those specific structural features—such as page count, title length, journal impact factor, quartile ranking, subject focus, and availability of financial support—significantly influence citation frequency. These parameters not only reflect the quality and rigor of the research but also serve as reliable indicators of overall scholarly impact and visibility. Furthermore, the findings underscore that during global emergencies, the rapid publication of robust, highly cited research in prestigious journals enhances scientific communication, fosters collaboration, and accelerates knowledge advancement. In essence, this analysis offers a solid foundation for refining future research methodologies and publication strategies, thereby promoting more effective scientific discourse and enabling a more coordinated response to emerging global challenges with lasting significance.

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References

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