ABSTRACT
Purpose: To assess the trustworthiness and impact of preprint trial reports during the COVID-19 pandemic. Data sources: WHO COVID-19 database and the L-OVE COVID-19 platform by the Epistemonikos Foundation (up to August 3rd, 2021) Design: We compare the characteristics of COVID-19 trials with and without preprints, estimate time to publication of COVID-19 preprint reports, describe discrepancies in key methods and results between preprint and published trial reports, report the number of retracted preprints and publications, and assess whether including versus excluding preprint reports affects meta-analytic estimates and the certainty of evidence. For the effects of eight therapies on mortality and mechanical ventilation, we performed meta-analyses including preprints and excluding preprints at 1 month, 3 months, and 6 months after the first trial addressing the therapy became available either as a preprint or publication (120 meta-analyses in total). Results: We included 356 trials, 101 of which are only available as preprints, 181 as journal publications, and 74 as preprints first and subsequently published in journals. Half of all preprints remain unpublished at six months and a third at one year. There were few important differences in key methods and results between trial preprints and their subsequent published reports. We identified four retracted trials, three of which were published in peer-reviewed journals. With two exceptions (2/60; 3.3%), point estimates were consistent between meta-analyses including versus excluding preprints as to whether they indicated benefit, no appreciable effect, or harm. There were nine comparisons (9/60; 15%) for which the rating of the certainty of evidence differed when preprints were included versus excluded, for four of these comparisons the certainty of evidence including preprints was higher and for five of these comparisons the certainty of evidence including preprints was lower. Limitations: The generalizability of our results is limited to COVID-19. Preprints that are subsequently published in journals may be the most rigorous and may not represent all trial preprints. Conclusion: We found no compelling evidence that preprints provide less trustworthy results than published papers. We show that preprints remain the only source of findings of many trials for several months, for a length of time that is unacceptable in a health emergency. We show that including preprints may affect the results of meta-analyses and the certainty of evidence. We encourage evidence users to consider data from preprints in contexts in which decisions are being made rapidly and evidence is being produced faster than can be peer-reviewed.
Subject(s)
COVID-19ABSTRACT
Objective To determine and compare the effects of drug prophylaxis on severe acute respiratory syndrome coronavirus virus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (covid-19). Design Living systematic review and network meta-analysis. Data sources WHO covid-19 database, a comprehensive multilingual source of global covid-19 literature to 19 January 2021, and six additional Chinese databases to 20 January 2021. Study selection Randomized trials in which people at risk of covid-19 were randomized to drug prophylaxis or no prophylaxis (standard care or placebo). Pairs of reviewers independently screened potentially eligible articles. Methods After duplicate data abstraction, we conducted random-effects bayesian network meta-analysis. We assessed risk of bias of the included studies using a modification of the Cochrane risk of bias 2.0 tool and assessed the certainty of the evidence using the grading of recommendations assessment, development and evaluation (GRADE) approach. Results The first iteration of this living network meta-analysis includes nine randomized trials: six addressing hydroxychloroquine (6,059 participants), one addressing ivermectin combined with iota-carrageenan (234 participants) and two addressing ivermectin alone (540 participants), all compared to standard care or placebo. Hydroxychloroquine has no important effect on admission to hospital (risk difference (RD) 1 fewer per 1,000, 95% credible interval (CrI) 3 fewer to 4 more, high certainty) or mortality (RD 1 fewer per 1,000, 95% CrI 2 fewer to 3 more, high certainty). Hydroxychloroquine probably has no important effect on laboratory-confirmed infection (RD 2 more per 1,000, 95% CrI 18 fewer to 28 more, moderate certainty), probably increases adverse effects leading to drug discontinuation (RD 19 more per 1,000, 95% CrI 1 fewer to 70 more, moderate certainty) and may have no important effect on suspected, probable or laboratory-confirmed infection (RD 15 fewer per 1,000, 95% CrI 64 fewer to 41 more, low certainty). Due to serious risk of bias and very serious imprecision, and thus very low certainty evidence, the effects of ivermectin combined with iota-carrageenan on laboratory-confirmed infection (RD 52 fewer per 1,000, 95% CrI 58 fewer to 37 fewer), and ivermectin alone on laboratory-confirmed infection (RD 50 fewer per 1,000, 95% CrI 59 fewer to 16 fewer) and suspected, probable or laboratory-confirmed infection (RD 159 fewer per 1,000, 95% CrI 165 fewer to 144 fewer) remain uncertain. Conclusion Hydroxychloroquine prophylaxis does not have an important effect on hospital admission and mortality, probably increases adverse effects, and probably does not have an important effect on laboratory-confirmed SARS-CoV-2 infection. Because of serious risk of bias and very serious imprecision, we are highly uncertain whether ivermectin combined with iota-carrageenan and ivermectin alone reduce the risk of SARS-CoV-2 infection. Systematic review registration This review was not registered. The protocol established a priori is included as a supplement. Funding This study was supported by the Canadian Institutes of Health Research (grant CIHR-IRSC:0579001321). Reader note This article is a living systematic review that will be updated to reflect emerging evidence. Updates may occur for up to two years from the date of original publication.
Subject(s)
Coronavirus Infections , Laboratory Infection , COVID-19ABSTRACT
Background: There are studies that show a chest CT scan is superior to reverse transcription-polymerase chain reaction (RT-PCR) studies in the diagnosis of COVID. This study was designed to assess the prevalence of COVID-related lung involvement in patients admitted to a trauma center.Methods: In a retrospective study, data from a regional referral trauma center from February 21, 2020 to April 10, 2020, were reviewed. All patients admitted to the hospital for whom a chest CT scan was performed during the study period for any reason were included. Trained physicians screened all CT-scans for findings suggestive of COVID-19. Next, blinded radiologists selected CT-scans with findings highly suggestive of COVID involvement. The clinical course and outcome, and the results of PCR for SARS-CoV-2 were recorded assessed.Results: A total of 4200 chest CT scans were reviewed. After multiple rounds of exclusion, 24 patients with highly- suggestive findings were reviewed. Only three patients developed COVID symptoms during the course of admission. PCR results were positive in 22 patients (92.6%). Conclusions: We suggest having a lower threshold for ordering chest CT scans in trauma patients at a high risk of COVID infection, as well as those requiring extensive surgical interventions. Also, a thorough review of the available CT scans before invasive procedures, preferably with the help of an expert radiologist, is highly recommended, even when the results of the COVID laboratory tests are negative.