key: cord-0972308-jhsml7vn authors: Teixeira da Silva, Jaime A.; Tsigaris, Panagiotis; Erfanmanesh, Mohammadamin title: Publishing volumes in major databases related to Covid-19 date: 2020-08-28 journal: Scientometrics DOI: 10.1007/s11192-020-03675-3 sha: 42543b4b5366d0f3c356676a91f285eb4a53a395 doc_id: 972308 cord_uid: jhsml7vn The SARS-CoV-2 virus, which causes Covid-19, induced a global pandemic for which an effective cure, either in the form of a drug or vaccine, has yet to be discovered. In the few brief months that the world has known Covid-19, there has been an unprecedented volume of papers published related to this disease, either in a bid to find solutions, or to discuss applied or related aspects. Data from Clarivate Analytics’ Web of Science, and Elsevier’s Scopus, which do not index preprints, were assessed. Our estimates indicate that 23,634 unique documents, 9960 of which were in common to both databases, were published between January 1 and June 30, 2020. Publications include research articles, letters, editorials, notes and reviews. As one example, amongst the 21,542 documents in Scopus, 47.6% were research articles, 22.4% were letters, and the rest were reviews, editorials, notes and other. Based on both databases, the top three countries, ranked by volume of published papers, are the USA, China, and Italy while BMJ, Journal of Medical Virology and The Lancet published the largest number of Covid-19-related papers. This paper provides one snapshot of how the publishing landscape has evolved in the first six months of 2020 in response to this pandemic and discusses the risks associated with the speed of publications. The global Covid-19 pandemic has already infected 13,734,518 people, causing 588,149 deaths 1 in one of humanity's greatest challenges of modern time. For academics, it has provided an extremely rare opportunity to examine so many aspects, biomedical and other (economic, public health, psychology, social, historical, etc.) , related to the SARS-CoV-2 virus. In just a few months, crudely tens of thousands of preprints and peer reviewed papers and other documents related to Covid-19 have been published. NCBI's LitCovid (Chen et al. 2020) shows that 31,360 documents had already been published on PubMed until July 14, 2020. The objective of this paper is to provide a snapshot of the publishing landscape to appreciate the volume of papers that have been published in indexed, peer reviewed journals in two major databases, Clarivate Analytics' Web of Science (WoS) and Elsevier's Scopus, from January 1 until June 30, 2020. More than 80% (83% in Scopus, 89% in WoS) of papers are open access (OA), but not all, despite a public agreement to make all papers OA. 2 We synthesize what we have discovered in these two databases. A brief discussion of some of the risks of the high publication volume of papers related to Covid-19 and the discrepancies between database findings is provided at the end of the letter. A search was limited, in WoS (SCI, SSCI, A&HCI and ESCI) and Scopus, to any documents published in the past six months (January 1 to June 30, 2020) using the search query "SARS-CoV-2" OR "COVID-19" OR "Coronavirus 2019" OR "Corona Virus 2019" OR "novel coronavirus" OR "novel corona virus" OR "2019-nCoV", in titles and keywords. Data was collected on July 1, 2020. As a result, 12,331 and 21,602 documents were retrieved from WoS and Scopus, respectively. These documents were then cleaned up manually in order to remove any duplicates. In a few cases, 2.3% in WoS and 0.28% in Scopus, early access and published versions of a same document were published twice with different accession numbers (in WoS) or Scopus IDs. Consequently, the sample sizes decreased to 12,052 documents with unique digital object identifiers (DOIs) or titles for WoS and 21,542 documents for Scopus. These records were then analyzed by a variety of fields including subject areas, document types, organizations, funding sponsors, authors, source titles, countries, languages, and most cited documents. We discovered 23,634 unique documents in WoS and Scopus, i.e., documents with unique DOIs or titles. More specifically, 2092 documents were exclusively indexed in WoS (but not in Scopus), 11,582 documents were exclusively indexed in Scopus (but not in WoS), and 9960 documents were indexed in both WoS and Scopus (Fig. 1) . (20) While analyzing the top-ranked authors (in terms of publishing volume), it was noticed that several Chinese authors were highly ranked. For example, in WoS, Wang Y, Zhang Y, Li Y and Liu Y were ranked 1st, 2nd, 3rd and 5th in the top 10 authors. Similarly, Wang L, Li L, Wang J and Liu J were ranked 6th to 9th. As one example, Wang Y, who should have been a "unique" author, and who had 76 papers attributed to his name, was in fact found, after manual disambiguation and analysis of the original records, be several Wang Y. 5 The importance of accurate, culturally-sensitive indexing of Chinese names cannot be over-emphasized as incorrectly indexed names can drastically alter author-based metrics (Teixeira da Silva 2020a, b) and, as can be observed in the statistics in the previous paragraph, metrics specifically related to Covid-19 literature. There are several techniques available to improve author name disambiguation (Hussain and Hasghar 2017) . One solution to solve the issue of name ambiguity is to inspect authors' names and their background information (e.g., the institution in which they worked or the research areas or topics in which they are active) prior to any further bibliometric study. Our analysis and data mining of two major citation databases indicates that 23,634 unique documents related to Covid-19 were published between January 1 and June 30, 2020. Fraser et al. (2020) also indicate that thousands of preprints have been published, accounting for roughly one third of the total volume of published papers related to Covid-19 in the January 1 to June 30 period. This sheer volume of papers related to a single topic may be unprecedented. These astonishing volumes of indexed papers and other documents related to Covid-19 in reputed databases are already placing pressure on academics to quickly publish their findings and their thoughts, and on editors and journals to rapidly release potentially medically important information that could be of value to health practitioners and policy makers alike. However, the publishing system is under pressure, and this may result in analytical errors (Ioannidis 2020) . The Covid-19 literature will require separate and thorough analyses to appreciate how this pandemic shaped the academic publishing sector. For example, a tiny fraction of the documents are corrections and retractions. These numbers may increase as Covid-19 papers, including preprints and papers in potentially predatory venues (Teixeira da Silva 2020a, b) are increasingly scrutinized. Results of the current research showed that 0.8% of the Covid-19 related documents in WoS (101 documents) and 0.5% of documents in Scopus (114 documents) have been corrected or retracted within a short time after publication. One notable aspect of the data summary in Tables 1, 2 and 3 (also see Fig. 1 ) are the sometimes-stark differences between Scopus and WoS, i.e., the choice of database for such analyses might bias the findings. Scopus tends to offer a more comprehensive coverage of the scientific and scholarly literature than WoS, and since Scopus collects a huge number Fig. 2 Example of a Scopus query, returning the same DOI mistakenly assigned to two papers (retrieved on July 14, 2020) Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. The Lancet Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: A descriptive study A novel coronavirus from patients with pneumonia in China Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: A retrospective cohort study Early transmission dynamics in Wuhan, China, of novel coronavirus-infected pneumonia A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: A study of a family cluster Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in china: Summary of a report of 72314 cases from the Chinese center for disease control and prevention Genomic characterization and epidemiology of 2019 novel coronavirus: Implications for virus origins and receptor binding First case of 2019 novel coronavirus in the United States by doing so, it can capture citations from documents that are not indexed in Scopus There are a few reasons for the predominance of documents in English, and apparent under-representation of Chinese: Scopus covers more Chinese-language documents than WoS, there are not many Chinese-language journals indexed in WoS, China has its own citation index (Chinese Science Citation Database) (Vera-Baceta et al. 2019), and most publications of authors affiliated with Chinese institutions were published in Englishlanguage journals. We recognize that the current study, which provides a six-month snapshot of two major databases, only gives a limited time-and database-based perspective Author contributions JATdaS, PT, and ME, who are co-corresponding authors, contributed equally to all parts of the study analysis, development, writing and interpretation Keep up with the latest coronavirus research Comparison of PubMed, Scopus, Web of Science, and Google Scholar: Strengths and weaknesses Preprinting a pandemic: the role of preprints in the COVID-19 pandemic. bioRxiv (preprint) A survey of author name disambiguation techniques Coronavirus disease 2019: The harms of exaggerated information and nonevidence-based measures Google Scholar, Web of Science, and Scopus: A systematic comparison of citations in 252 subject categories The journal coverage of Web of Science and Scopus: A comparative analysis Chinese names in the biomedical literature: Suggested bibliometric standardization An alert to COVID-19 literature in predatory publishing venues Web of science and Scopus language coverage Conflict of interest The authors declare that they have no conflict of interest.