每天发表近 80 篇系统评价：2000 年至 2019 年流行病学趋势和报告的观察性研究。

Nearly 80 systematic reviews were published each day: Observational study on trends in epidemiology and reporting over the years 2000-2019.

机构信息

Department of Health Services Research, School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany.

出版信息

J Clin Epidemiol. 2021 Oct;138:1-11. doi: 10.1016/j.jclinepi.2021.05.022. Epub 2021 Jun 4.

DOI:10.1016/j.jclinepi.2021.05.022

PMID:34091022

Abstract

BACKGROUND

Systematic reviews (SRs) are useful tools in synthesising the available evidence, but high numbers of overlapping SRs are also discussed in the context of research waste. Although it is often claimed that the number of SRs being published is increasing steadily, there are no precise data on that. We aimed to assess trends in the epidemiology and reporting of published SRs over the last 20 years.

METHODS

A retrospective observational study was conducted to identify potentially eligible SRs indexed in PubMed from 2000 to 2019. From all 572,871 records retrieved, we drew a simple random sample of 4,000. The PRISMA-P definition of SRs was applied to full texts and only SRs published in English were included. Characteristics were extracted by one reviewer, with a 20% sample verified by a second person.

RESULTS

A total of 1,132 SRs published in 710 different journals were included. The estimated number of SRs indexed in 2000 was 1,432 (95% CI: 547-2,317), 5,013 (95% CI: 3,375-6,650) in 2010 and 29,073 (95% CI: 25,445-32,702) in 2019. Transparent reporting of key items increased over the years. About 7 out of 10 named their article a SR (2000-2004: 41.9% and 2015-2019: 74.4%). In 2000-2004, 32.3% of SRs were based in the UK (0% in China), in 2015-2019 24.0% were from China and 10.8% from the UK. Nearly all articles from China (94.9%) conducted a meta-analysis (overall: 58.9%). Cochrane reviews (n = 84; 7.4%) less often imposed language restrictions, but often did not report the number of records and full texts screened and did not name their article a SR (22.6% vs. 73.4%).

CONCLUSIONS

We observed a more than 20-fold increase in the number of SRs indexed over the last 20 years. In 2019, this is equivalent to 80 SRs per day. Over time, SRs got more diverse in respect to journals, type of review, and country of corresponding authors. The high proportion of meta-analyses from China needs further investigation.

STUDY REGISTRATION

Open Science Framework (https://osf.io/pxjrv/).

摘要

背景

系统评价（SRs）是综合现有证据的有用工具，但在研究浪费的背景下也讨论了大量重叠的 SRs。尽管人们经常声称发表的 SRs 数量正在稳步增加，但实际上并没有确切的数据。我们旨在评估过去 20 年来发表的 SRs 的流行病学和报告趋势。

方法

本研究采用回顾性观察性研究，旨在确定从 2000 年至 2019 年在 PubMed 中索引的潜在合格 SRs。从检索到的 572,871 条记录中，我们抽取了简单随机样本 4,000 条。应用 PRISMA-P 对全文进行了 SR 定义，并仅纳入了以英文发表的 SRs。由一名评审员提取特征，另一名评审员对 20%的样本进行了验证。

结果

共纳入了 710 种不同期刊发表的 1,132 篇 SRs。2000 年索引的 SRs 估计数量为 1,432（95%CI：547-2,317），2010 年为 5,013（95%CI：3,375-6,650），2019 年为 29,073（95%CI：25,445-32,702）。关键项目的透明报告逐年增加。大约每 10 篇文章中就有 7 篇将其文章命名为 SR（2000-2004 年：41.9%，2015-2019 年：74.4%）。2000-2004 年，来自英国的 SRs 占 32.3%（中国为 0%），2015-2019 年，来自中国的占 24.0%，来自英国的占 10.8%。几乎所有来自中国的文章（94.9%）都进行了荟萃分析（总体：58.9%）。 Cochrane 评论（n=84；7.4%）较少施加语言限制，但通常未报告筛选的记录和全文数量，也未将其文章命名为 SR（22.6%比 73.4%）。