We identified 651 research outputs on the topic of COVID-19 in the form of preprint, report, journal article, dataset, and software/code published by Imperial College London authors between January to September 2020. We sought to understand the distribution of outputs over time by output type, peer review status, publisher, and open access status. Search of Scopus, the institutional repositories, Github, and other databases identified relevant research outputs, which were then combined with Unpaywall open access data and manually-verified associations between preprints and journal articles. Reports were the earliest output to emerge [median: 103 days, interquartile range (IQR): 57.5–129], but journal articles were the most commonly occurring output type over the entire period (60.8%, 396/651). Thirty preprints were identified as connected to a journal article within the set (15.8%, 30/189). A total of 52 publishers were identified, of which 4 publishers account for 59.6% of outputs (388/651). The majority of outputs were available open access through gold, hybrid, or green route (66.1%, 430/651). The presence of exclusively non-peer reviewed material from January to March suggests that demand could not be met by journals in this period, and the sector supported this with enhanced preprint services for authors. Connections between preprints and published articles suggests that some authors chose to use both dissemination methods and that, as some publishers also serve across both models, traditional distinctions of output types might be changing. The bronze open access cohort brings widespread ‘free’ access but does not ensure true open access.

中文翻译：

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伦敦帝国学院 COVID-19 研究成果的特点

我们确定了伦敦帝国理工学院作者在 2020 年 1 月至 9 月期间发表的 651 项关于 COVID-19 主题的研究成果，其形式包括预印本、报告、期刊文章、数据集和软件/代码。我们试图了解这些成果的分布情况按输出类型、同行评审状态、出版商和开放获取状态划分的时间。对 Scopus、机构知识库、Github 和其他数据库的搜索确定了相关的研究成果，然后将其与 Unpaywall 开放获取数据以及预印本和期刊文章之间手动验证的关联相结合。报告是最早出现的输出类型[中位数：103 天，四分位距 (IQR)：57.5–129]，但期刊文章是整个期间最常见的输出类型（60.8%，396/651）。三十份预印本被确定为与该集中的一篇期刊文章相关（15.8%，30/189）。总共确定了 52 个出版商，其中 4 个出版商占产出的 59.6% (388/651)。大多数产出可通过黄金、混合或绿色路线开放获取（66.1%，430/651）。1 月至 3 月出现的完全未经同行评审的材料表明，期刊在此期间无法满足需求，该部门通过加强为作者提供的预印本服务来支持这一点。预印本和已发表文章之间的联系表明，一些作者选择使用这两种传播方法，并且由于一些出版商也跨这两种模式提供服务，因此输出类型的传统区别可能正在发生变化。铜牌开放获取队列带来了广泛的“免费”获取，但并不能确保真正的开放获取。