Coronavirus disease (COVID-19) pandemic: an overview of systematic reviews

  1. Israel Júnior Borges do Nascimento
  2. Dónal P. O’Mathúna
  3. Thilo Caspar von Groote
  4. Hebatullah Mohamed Abdulazeem
  5. Ishanka Weerasekara
  6. Ana Marusic
  7. Livia Puljak
  8. Vinicius Tassoni Civile
  9. Irena Zakarija-Grkovic
  10. Tina Poklepovic Pericic
  11. Alvaro Nagib Atallah
  12. Santino Filoso
  13. Nicola Luigi Bragazzi
  14. Milena Soriano Marcolino
  15. On behalf of the International Network of Coronavirus Disease 2019 (InterNetCOVID-19)

Reviewed by

Read the full article See related articles

Listed in

Log in to save this article

Abstract

Background

Navigating the rapidly growing body of scientific literature on the SARS-CoV-2 pandemic is challenging, and ongoing critical appraisal of this output is essential. We aimed to summarize and critically appraise systematic reviews of coronavirus disease (COVID-19) in humans that were available at the beginning of the pandemic.

Methods

Nine databases (Medline, EMBASE, Cochrane Library, CINAHL, Web of Sciences, PDQ-Evidence, WHO’s Global Research, LILACS, and Epistemonikos) were searched from December 1, 2019, to March 24, 2020. Systematic reviews analyzing primary studies of COVID-19 were included. Two authors independently undertook screening, selection, extraction (data on clinical symptoms, prevalence, pharmacological and non-pharmacological interventions, diagnostic test assessment, laboratory, and radiological findings), and quality assessment (AMSTAR 2). A meta-analysis was performed of the prevalence of clinical outcomes.

Results

Eighteen systematic reviews were included; one was empty (did not identify any relevant study). Using AMSTAR 2, confidence in the results of all 18 reviews was rated as “critically low”. Identified symptoms of COVID-19 were (range values of point estimates): fever (82–95%), cough with or without sputum (58–72%), dyspnea (26–59%), myalgia or muscle fatigue (29–51%), sore throat (10–13%), headache (8–12%) and gastrointestinal complaints (5–9%). Severe symptoms were more common in men. Elevated C-reactive protein and lactate dehydrogenase, and slightly elevated aspartate and alanine aminotransferase, were commonly described. Thrombocytopenia and elevated levels of procalcitonin and cardiac troponin I were associated with severe disease. A frequent finding on chest imaging was uni- or bilateral multilobar ground-glass opacity. A single review investigated the impact of medication (chloroquine) but found no verifiable clinical data. All-cause mortality ranged from 0.3 to 13.9%.

Conclusions

In this overview of systematic reviews, we analyzed evidence from the first 18 systematic reviews that were published after the emergence of COVID-19. However, confidence in the results of all reviews was “critically low”. Thus, systematic reviews that were published early on in the pandemic were of questionable usefulness. Even during public health emergencies, studies and systematic reviews should adhere to established methodological standards.

Article activity feed

  1. Version published to 10.1186/s12879-021-06214-4
  2. ScreenIT

    SciScore for 10.1101/2020.04.16.20068213: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board StatementIRB: Ethics: Approval of a research ethics committee was not necessary as the study analyzed only publicly available articles. 2.3. Eligibility Criteria: Systematic reviews were included if they analyzed primary data from patients infected with SARS-CoV-2 as confirmed by RT-PCR or another pre-specified diagnostic technique.
    RandomizationQuality Assessment in Individual Reviews: Two researchers independently assessed the quality of the reviews using the “A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR 2)”, designed to assess systematic reviews that include both randomized and non-randomized studies.
    Blindingnot detected.
    Power Analysisnot detected.
    Sex as a biological variableThe following were categorized as exploratory outcomes: diagnostic methods used for detection of the virus, male to female ratio, clinical symptoms, pharmacological and non-pharmacological interventions, laboratory findings (full blood count, liver enzymes, C-reactive protein, d-dimer, albumin, lipid profile, serum electrolytes, blood vitamin levels, glucose levels, and any other important biomarkers), and radiological findings (using radiography, computed tomography, magnetic resonance imaging or ultrasound).

    Table 2: Resources

    Software and Algorithms
    SentencesResources
    The methodology used in this review was adapted from the Cochrane Handbook for Systematic Reviews of Interventions and also followed established methodological considerations for analyzing existing systematic reviews [10,11]. 2.2.
    Cochrane Handbook
    suggested: None
    We excluded narrative reviews as these are less likely to be replicable and are more prone to bias. 2.4. Information Sources: Nine databases were searched for eligible records published between December 1 2019 and March 24, 2020: Cochrane Database of Systematic Reviews via Cochrane Library, PubMed EMBASE
    Cochrane Library
    suggested: (Cochrane Library, RRID:SCR_013000)
    PubMed
    suggested: (PubMed, RRID:SCR_004846)
    All retrieved records were primarily processed in EndNote, where duplicates were removed, and records were then imported on Covidence Platform [12].
    EndNote
    suggested: (EndNote, RRID:SCR_014001)
    We developed the using RStudio© software, with the “metafor” package (version 2.1-0) and “forest” function.
    RStudio©
    suggested: None

    Results from OddPub: Thank you for sharing your data.

    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    A limitation of our study is that for AMSTAR 2 assessment we relied on information available in publications; we did not attempt to contact study authors for clarifications or additional data. Appraisal of methodological quality of three reviews was hindered because they were published as letters, labelled as rapid communications. As a result, various details about their review process were not included, leading to AMSTAR 2 questions being answered as not reported and thus to low confidence scores. Full manuscripts might have provided additional information that could have led to higher confidence in the results. In other words, low scores could reflect incomplete reporting, not necessarily low quality review methods. In seeking to make their review available more rapidly and more concisely, methodological details may have been omitted. This reflects a general issue during a crisis where speed and completeness must be balanced. Given that some included reviews scored “high”, the two factors are not mutually exclusive. However, this requires proper resourcing and commitment to ensure users of systematic reviews can have high confidence in the results. Despite this limitation, this overview adds to the current knowledge by providing a comprehensive summary of all the currently available evidence about COVID-19 from published systematic reviews. This overview followed strict methodological criteria, including a comprehensive and sensitive search strategy and a standard tool for ...

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  3. Version published to 10.1101/2020.04.16.20068213 on medRxiv