Impact of the COVID-19 pandemic on publication dynamics and non-COVID-19 research production

Abstract

Background: The COVID-19 pandemic has severely affected health systems and medical research worldwide but its impact on the global publication dynamics and non-COVID-19 research has not been measured. We hypothesized that the COVID-19 pandemic may have impacted the scientific production of non-COVID-19 research.

Methods: We conducted a comprehensive meta-research on studies (original articles, research letters and case reports) published between 01/01/2019 and 01/01/2021 in 10 high-impact medical and infectious disease journals (New England Journal of Medicine, Lancet, Journal of the American Medical Association, Nature Medicine, British Medical Journal, Annals of Internal Medicine, Lancet Global Health, Lancet Public Health, Lancet Infectious Disease and Clinical Infectious Disease). For each publication, we recorded publication date, publication type, number of authors, whether the publication was related to COVID-19, whether the publication was based on a case series, and the number of patients included in the study if the publication was based on a case report or a case series. We estimated the publication dynamics with a locally estimated scatterplot smoothing method. A Natural Language Processing algorithm was designed to calculate the number of authors for each publication. We simulated the number of non-COVID-19 studies that could have been published during the pandemic by extrapolating the publication dynamics of 2019 to 2020, and comparing the expected number to the observed number of studies.

Results: Among the 22,525 studies assessed, 6319 met the inclusion criteria, of which 1022 (16.2%) were related to COVID-19 research. A dramatic increase in the number of publications in general journals was observed from February to April 2020 from a weekly median number of publications of 4.0 (IQR: 2.8-5.5) to 19.5 (IQR: 15.8-24.8) (p < 0.001), followed afterwards by a pattern of stability with a weekly median number of publications of 10.0 (IQR: 6.0-14.0) until December 2020 (p = 0.045 in comparison with April). Two prototypical editorial strategies were found: 1) journals that maintained the volume of non-COVID-19 publications while integrating COVID-19 research and thus increased their overall scientific production, and 2) journals that decreased the volume of non-COVID-19 publications while integrating COVID-19 publications. We estimated using simulation models that the COVID pandemic was associated with a 18% decrease in the production of non-COVID-19 research. We also found a significant change of the publication type in COVID-19 research as compared with non-COVID-19 research illustrated by a decrease in the number of original articles, (47.9% in COVID-19 publications vs 71.3% in non-COVID-19 publications, p < 0.001). Last, COVID-19 publications showed a higher number of authors, especially for case reports with a median of 9.0 authors (IQR: 6.0-13.0) in COVID-19 publications, compared to a median of 4.0 authors (IQR: 3.0-6.0) in non-COVID-19 publications (p < 0.001).

Conclusion: In this meta-research gathering publications from high-impact medical journals, we have shown that the dramatic rise in COVID-19 publications was accompanied by a substantial decrease of non-COVID-19 research. META-RESEARCH REGISTRATION: https://osf.io/9vtzp/ .

Keywords: COVID-19; High-impact journals; Meta-research; Publications.

Fig. 1

Study flowchart. The flowchart depicts the review process and the inclusion/exclusion criteria. PubMed data source were used for identifying publications from the 10 high-impact medical journals included in the present study (New England Journal of Medicine, Lancet, Journal of the American Medical Association, Nature Medicine, British Medical Journal, Annals of Internal Medicine, Lancet Infectious Disease, Lancet Global Health, Lancet Public Health and Clinical Infectious Disease). We did not retrieve any additional publications with manual search

Fig. 2

Weekly number of COVID-19 and non-COVID-19 publications with original data. These graphs show the publication dynamics in the journals included, from January 1st 2019 to January 1st 2021. We present in Panel A the top six general journals (New England Journal of Medicine, Lancet, Journal of American Medical Association, Nature Medicine, British Medical Journal, and Annals of Internal Medicine), given the distinct distribution in journals related to infectious diseases and public health. We present the distribution in all journals in supplementary Fig. 1. Panel B shows the distribution in each journal. A. Overall. B. Per Journal

Fig. 3

Publication type and COVID-19. This graph shows the distribution of the COVID-19 publications and non-COVID-19 publications, stratified per publication type (original articles, research letters, and case reports). A chi² test was performed to assess the difference between the distributions. The distribution of the COVID-19 publications and non-COVID-19 publications, stratified per publication type in general journals is presented in supplementary Fig. 4

Fig. 4

COVID-19 publications and the number of authors dynamics. This graph shows the dynamics of number of authors in COVID-19 publications and non-COVID-19 publications, stratified per publication type (original articles, research letters, case reports). The dynamics of number of authors in COVID-19 publications and non-COVID-19 publications, stratified per publication type, in general journals are presented in supplementary Fig. 5

Fig. 5

COVID-19 publications and author multiplicity. This graph shows the number of authors in COVID-19 publications and non-COVID-19 publications, stratified per publication type (original articles, research letters, and case reports). The article based on case series comprised original articles and research letters based on case series. A Wilcoxon test was performed to assess the difference between the distributions. The number of authors in COVID-19 publications and non-COVID-19 publications, stratified per publication type, in general journals is presented in the supplementary Fig. 6