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PurposeTo assess the trustworthiness and impact of preprint trial reports during the COVID-19 pandemic. Data sourcesWHO COVID-19 database and the L-OVE COVID-19 platform by the Epistemonikos Foundation (up to August 3rd, 2021) DesignWe 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). ResultsWe 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 Half of all preprints remain unpublished at six months and a third at one year.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. LimitationsThe 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. ConclusionWe 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, 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. O_TEXTBOXSummary Box 1O_ST_ABSWhat is already known on this topicC_ST_ABSO_LIClinicians and decision-makers need rapidly available and credible data addressing the comparative effectiveness of treatments and prophylaxis for COVID-19. C_LIO_LIInvestigators have adopted preprint servers, which allow the rapid dissemination of research findings before publication in peer-reviewed journals. C_LI What this study addsO_LIWe found no compelling evidence that preprints provide less trustworthy results than published papers. C_LIO_LIWe show that including preprints may affect the results of meta-analyses and the certainty of evidence and 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. C_LI C_TEXTBOX
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BackgroundRecent evidence indicates a potential therapeutic role of fluvoxamine for COVID-19. In the TOGETHER randomized platform clinical trial for acutely symptomatic patients with COVID-19, we assessed the efficacy of fluvoxamine vs. placebo in preventing either extended emergency room observation or hospitalization due to COVID-19. Herein, we report the preliminary findings. MethodsThis placebo-controlled, randomized, adaptive, platform trial conducted among symptomatic Brazilian adults confirmed positive for SARS-CoV-2 included eligible patients with a known risk factor for progression to severe disease. Patients were randomly assigned to either fluvoxamine (100 mg twice daily for 10 days) or placebo. The primary endpoint was a composite outcome of emergency room observation for >6 hours or hospitalization from COVID-19 up to 28 days post randomization using intention to treat. Modified intention to treat (mITT) explored patients receiving at least 24 hours of treatment before a primary outcome event. Secondary outcomes included viral clearance at day 7, time to hospitalization, mortality, and adverse drug reactions. We used a Bayesian analytic framework to determine effects along with probability of success of intervention compared to placebo. The trial is registered at clinicaltrials.gov (NCT04727424) and is ongoing. FindingsThe study team screened 9020 potential participants for this trial. The trial was initiated on June 2, 2020, with the current protocol reporting randomization from January 15, 2021 to August 6th 2021, when the trial arms were stopped for superiority. A total of 3238 patients were allocated to fluvoxamine (n=739), placebo (n=733) and other treatments (n=1766). Herein, we report the effectiveness of fluvoxamine vs. a concurrent placebo control. The average age of participants was 50 years (range 18-102 years); 57% were female. The proportion of patients observed in an emergency room for >6 hours or admitted to hospital due to COVID-19 was lower for the fluvoxamine group compared to placebo (77/739 vs 108/733; Relative Risk [RR]: 0.71; 95% Bayesian Credible Interval [95% BCI]: 0.54 - 0.93), with a probability of superiority of 99.4% surpassing the prespecified superiority threshold of 97.6% (risk difference 4.3%). Of the composite primary outcome events, 88% were hospitalizations. Findings were similar for the mITT analysis (RR0.68, 95% BCI : 0.50- 0.91). We found no significant relative effects between the fluvoxamine and placebo groups on viral clearance at day 7 (Odds ratio [OR]: 0.75; 95% Confidence Intervals [95% CI]: 0.53 - 1.07), mortality (OR: 0.70; 95% CI: 0.36 - 1.30), time to death (Hazard ratio [HR]: 0.79; 95% CI: 0.58 - 1.08), days hospitalized (Mean Difference (MD) 1.22 days; 95% CI: 0.98 - 1.53), number of days ventilated (MD 1.10; 95% CI: 0.70 - 1.73) or other secondary outcomes. Data capturing all 28 days of follow-up will be reported after August 26th, 2021. InterpretationTreatment with fluvoxamine (100 mg twice daily for 10 days) among high-risk outpatients with early diagnosed COVID-19, reduced the need for extended emergency room observation or hospitalization. FundingThe trial was supported by FastGrants and The Rainwater Foundation.
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OBJECTIVES: The purpose of this systematic review was to investigate the association between dietary intake of citrus fruits and prostate cancer risk. METHODS: Authors searched electronic databases and the reference lists of publications of diet and prostate cancer studies until August 2007. All of the epidemiological studies that obtained individual data on dietary intake of citrus fruits and presented risk estimates of the association between intake of citrus fruits and risk of prostate cancer were identified and included. Using general variance-based methods, study-specific odds ratios (OR)/ relative risk (RR) and associated confidence interval (CI)/ standard error (SE) for highest versus lowest intake of citrus fruits level were extracted from each paper. RESULTS: Eleven articles including six case-control studies, one nested case-control study and four cohort studies, proved eligible. Overall summary OR using random effect model did not show an association in risk of prostate caner with intake of citrus fruits (summary OR=1.03, 95% CI=0.89-1.19) with large heterogeneity across studies that we were unable to explain (I(2)=67.88%). The summary ORs in case-control studies and cohort studies were 1.10 (95% CI=0.97-1.22) and 1.05 (95% CI=0.96-1.14), respectively. CONCLUSIONS: Pooled results from observational studies did not show an association between intake of citrus fruits and the risk of prostate cancer, although results vary substantially across studies.
