Department of Respiratory Medicine, Amsterdam University Medical Centres, University of Amsterdam, The Netherlands.
Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada.
Res Synth Methods. 2020 May;11(3):343-353. doi: 10.1002/jrsm.1389. Epub 2020 Feb 5.
Many diagnostic accuracy studies are never reported in full in a peer-reviewed journal. Searching for unpublished studies may avoid bias due to selective publication, enrich the power of systematic reviews, and thereby help to reduce research waste. We assessed searching practices among recent systematic reviews of diagnostic accuracy.
We extracted data from 100 non-Cochrane systematic reviews of diagnostic accuracy indexed in MEDLINE and published between October 2017 and January 2018 and from all 100 Cochrane systematic reviews of diagnostic accuracy published by December 2018, irrespective of whether meta-analysis had been performed.
Non-Cochrane and Cochrane reviews searched a median of 4 (IQR 3-5) and 6 (IQR 5-9) databases, respectively; most often MEDLINE/PubMed (n = 100 and n = 100) and EMBASE (n = 81 and n = 100). Additional efforts to identify studies beyond searching bibliographic databases were performed in 76 and 98 reviews, most often through screening reference lists (n = 71 and n = 96), review/guideline articles (n = 18 and n = 52), or citing articles (n = 3 and n = 42). Specific sources of unpublished studies were searched in 22 and 68 reviews, for example, conference proceedings (n = 4 and n = 18), databases only containing conference abstracts (n = 2 and n = 33), or trial registries (n = 12 and n = 39). At least one unpublished study was included in 17 and 23 reviews. Overall, 39 of 2082 studies (1.9%) included in non-Cochrane reviews were unpublished, and 64 of 2780 studies (2.3%) in Cochrane reviews, most often conference abstracts (97/103).
Searching practices vary considerably across systematic reviews of diagnostic accuracy. Unpublished studies are a minimal fraction of the evidence included in recent reviews.
许多诊断准确性研究从未在同行评审期刊上完整报告。搜索未发表的研究可以避免由于选择性发表而导致的偏倚，丰富系统评价的效能，从而有助于减少研究浪费。我们评估了最近诊断准确性系统评价中搜索实践的情况。
我们从 2017 年 10 月至 2018 年 1 月在 MEDLINE 中索引的 100 项非 Cochrane 诊断准确性系统评价和 2018 年 12 月之前发表的所有 100 项 Cochrane 诊断准确性系统评价中提取数据，无论是否进行了荟萃分析。
非 Cochrane 和 Cochrane 综述分别检索了中位数为 4（IQR 3-5）和 6（IQR 5-9）个数据库；最常用的是 MEDLINE/PubMed（n = 100 和 n = 100）和 EMBASE（n = 81 和 n = 100）。在 76 项和 98 项综述中，还进行了其他额外的努力来确定超出检索文献数据库的研究，最常见的是通过筛选参考文献（n = 71 和 n = 96）、综述/指南文章（n = 18 和 n = 52）或引用文章（n = 3 和 n = 42）。在 22 项和 68 项综述中，搜索了特定的未发表研究来源，例如会议记录（n = 4 和 n = 18）、仅包含会议摘要的数据库（n = 2 和 n = 33）或试验注册处（n = 12 和 n = 39）。在 17 项和 23 项综述中，至少纳入了一项未发表的研究。总体而言，在非 Cochrane 综述中纳入的 2082 项研究中有 39 项（1.9%）为未发表的研究，在 Cochrane 综述中纳入的 2780 项研究中有 64 项（2.3%）为未发表的研究，最常见的是会议摘要（97/103）。
诊断准确性系统评价的搜索实践差异很大。未发表的研究在最近的综述中仅占证据的一小部分。
