Cited by 253Academic Publishing and Open AccessBiomedical Text Mining and OntologiesSARS-CoV-2 and COVID-19 Research

LitCovid: an open database of COVID-19 literature

Open access
Chen, Qingyu, Allot, Alexis, Lu, Zhiyong·2021·Nucleic Acids Research

Abstract

Since the outbreak of the current pandemic in 2020, there has been a rapid growth of published articles on COVID-19 and SARS-CoV-2, with about 10 000 new articles added each month. This is causing an increasingly serious information overload, making it difficult for scientists, healthcare professionals and the general public to remain up to date on the latest SARS-CoV-2 and COVID-19 research. Hence, we developed LitCovid (https://www.ncbi.nlm.nih.gov/research/coronavirus/), a curated literature hub, to track up-to-date scientific information in PubMed. LitCovid is updated daily with newly identified relevant articles organized into curated categories. To support manual curation, advanced machine-learning and deep-learning algorithms have been developed, evaluated and integrated into the curation workflow. To the best of our knowledge, LitCovid is the first-of-its-kind COVID-19-specific literature resource, with all of its collected articles and curated data freely available. Since its release, LitCovid has been widely used, with millions of accesses by users worldwide for various information needs, such as evidence synthesis, drug discovery and text and data mining, among others.

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Crossref · 10.1093/nar/gkaa952

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  • The evaluation on the LitCovid dataset shows the model achieved high performance in classifying COVID-19 related articles because many COVID-19 related articles have explicit terms and the dataset is large enough.

    “This evaluation shows that the model achieved high performance in classifying COVID-19 related articles because many COVID-19 related articles have explicit terms to describe COVID-19 and SARS-COV-2, and the dataset is large enough for machine learning models.”

    From LitSuggest: a web-based system for literature recommendation and curation using machine learning (2021) · cites this paper as [8]

    The Results section, “Evaluation performance of automated methods in curation assistance” (page not provided), reports a document-classification F1-score of 0.99 on LitCovid evaluation data, with 63,998 training and 16,000 test articles. It does not attribute that performance to articles using explicit COVID-19 terms or state that the dataset was large enough to produce the result. (LLM, conf=0.88)

    Experimental — accuracy not yet measured
  • LitSuggest identified about 30% more COVID-19 related articles than keyword searches.

    “We found that LitSuggest identified about 30% more COVID-19 related articles than keyword searches, suggesting that machine learning models handle the high variability and ambiguity of terms describing COVID-19 and SARS-COV-2 in the literature (8) more effectively.”

    From LitSuggest: a web-based system for literature recommendation and curation using machine learning (2021) · cites this paper as [8]

    The Results section (‘Comparison of LitCovid versus keyword query’) reports that LitCovid contained 593 COVID-19 papers versus 457 retrieved by a PubMed keyword query—approximately 30% more. The Methods section (‘Document triage’) describes LitSuggest as a system that streamlines manual review and curation; the paper does not attribute the 30% difference to LitSuggest alone. (LLM, conf=0.88)

    Experimental — accuracy not yet measured
  • Existing query-based search systems such as PubMed often return suboptimal results, missing some publications while returning some that are irrelevant.

    “As such, existing query-based search systems such as PubMed and many others often return suboptimal results (8,12): missing some publications while returning some that are irrelevant.”
  • LitSuggest models achieved an F1-score of 0.99 on identifying COVID-19 related papers.

    “The performance of LitSuggest models on identifying COVID-19 related papers (See evaluation section) was evaluated in detail, and the models achieved an F1-score of 0.99 (the training and testing datasets are also publicly available) (8).”

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Research works printed but not linked: 2

  1. [7]Wang L.L., Lo K., Chandrasekhar Y., Reas R., Yang J., Eide D., Funk K., Kinney R., Liu Z., Merrill W. CORD-19: the Covid-19 open research dataset. ACL NLP-COVID Workshop. 2020; 2020:
  2. [14]Chen Q., Peng Y., Lu Z. BioSentVec: creating sentence embeddings for biomedical texts. 2019 IEEE International Conference on Healthcare Informatics (ICHI). 2019; 1– 5.

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Authors
Chen, Q., Allot, A., & Lu, Z.
Affiliations
National Institutes of Health (US)
Corresponding author
Lu, Zhiyong
Venue
Nucleic Acids Research
Published
2020-11-09
Volume
49
Issue
D1
Pages
D1534-D1540
ISSN
  • 0305-1048 (ISSN-L)
  • 1362-4962
OpenAlex
W3105753785
Cited by
253
References
27
Citations by year
2026: 8 · 2025: 15 · 2024: 29 · 2023: 54 · 2022: 81 · 2021: 61 · 2020: 4
FWCI
50.08
Type
journal article
Language
en
Open access
Licence
public-domain
Locations
  • Nucleic Acids Research (publishedVersion, public-domain)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • Intramural Research Program of the National Library of Medicine
  • National Institutes of Health
Topics
  • Social Sciences › Decision Sciences › Information Systems and Management › Academic Publishing and Open Access
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Biomedical Text Mining and Ontologies
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
Keywords
COVID-19 pandemic, SARS-CoV-2, literature curation, information overload, deep learning, PubMed, evidence synthesis, drug discovery, text and data mining
MeSH terms
Machine Learning, COVID-19, SARS-CoV-2, Humans, Publications, Databases, Factual, Internet, PubMed, Data Mining, Pandemics, Data Curation

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