University Hospital and School of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Medical College of Wisconsin, Milwaukee, WI, USA.
BMC Infect Dis. 2021 Jun 4;21(1):525. doi: 10.1186/s12879-021-06214-4.
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.
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.
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%.
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.
应对不断增长的关于 SARS-CoV-2 大流行的科学文献具有挑战性，持续对这些文献进行批判性评估至关重要。我们的目的是总结和批判性评估大流行初期可用的关于人类冠状病毒病（COVID-19）的系统评价。
从 2019 年 12 月 1 日至 2020 年 3 月 24 日，在 9 个数据库（Medline、EMBASE、Cochrane 图书馆、CINAHL、Web of Sciences、PDQ-Evidence、世界卫生组织全球研究、LILACS 和 Epistemonikos）中进行了搜索。纳入分析 COVID-19 原始研究的系统评价。两名作者独立进行了筛选、选择、提取（临床症状、患病率、药物和非药物干预、诊断测试评估、实验室和影像学发现的数据）和质量评估（AMSTAR 2）。对临床结局的患病率进行了 meta 分析。
纳入了 18 项系统评价，其中 1 项为空（未发现任何相关研究）。使用 AMSTAR 2，对所有 18 项评价的结果的置信度评为“极低”。确定的 COVID-19 症状为（点估计值的范围值）：发热（82-95%）、咳嗽伴或不伴咳痰（58-72%）、呼吸困难（26-59%）、肌痛或肌肉疲劳（29-51%）、咽痛（10-13%）、头痛（8-12%）和胃肠道症状（5-9%）。男性中更常见严重症状。描述了常见的升高 C 反应蛋白和乳酸脱氢酶，以及略升高的天门冬氨酸和丙氨酸氨基转移酶。血小板减少症以及降钙素原和心肌肌钙蛋白 I 水平升高与严重疾病相关。胸部影像学的常见表现为单侧或双侧多叶磨玻璃影。一项综述研究了药物（氯喹）的影响，但未发现可验证的临床数据。全因死亡率为 0.3%至 13.9%。
在本系统评价概述中，我们分析了 COVID-19 出现后发表的前 18 项系统评价中的证据。然而，所有评价结果的可信度都“极低”。因此，大流行早期发表的系统评价实用性值得怀疑。即使在突发公共卫生事件期间，研究和系统评价也应遵守既定的方法学标准。
