Abstract：
Risk of bias (RoB) assessment is essential to the systematic review methodology. The new version of the Cochrane RoB tool for randomized trials (RoB 2) was published in 2019 to address limitations identified since the first version of the tool was published in 2008 and to increase the reliability of assessments. This study analyzed the frequency of usage of the RoB 2 and the adequacy of reporting the RoB 2 assessments in non-Cochrane reviews published in 2020. This meta-research study included non-Cochrane systematic reviews of interventions published in 2020. For the reviews that used the RoB 2 tool, we analyzed the reporting of the RoB 2 assessment. Among 3880 included reviews, the Cochrane RoB 1 tool was the most frequently used (N = 2228; 57.4%), followed by the Cochrane RoB 2 tool (N = 267; 6.9%). From 267 reviews that reported using the RoB 2 tool, 213 (79.8%) actually used it. In 26 (12.2%) reviews, erroneous statements were used to indicate the RoB 2 assessment. Only 20 (9.4%) reviews presented a complete RoB 2 assessment with a detailed table of answers to all signaling questions. The judgment of risk of bias by the RoB 2 tool was not justified by a comment in 158 (74.2%) reviews. Only in 33 (14.5%) of reviews the judgment in all domains was justified in the accompanying comment. In most reviews (81.7%), the RoB was inadequately assessed at the study level. In conclusion, the majority of non-Cochrane reviews published in 2020 still used the Cochrane RoB 1 tool. Many reviews used the RoB 2 tool inadequately. Further studies about the uptake and the use of the RoB 2 tool are needed.
摘要：
偏见风险(RoB)评估对于系统评价方法至关重要。用于随机试验的CochraneRoB工具（RoB2）的新版本于2019年发布，以解决自2008年发布该工具的第一个版本以来发现的局限性，并提高评估的可靠性。这项研究分析了RoB2的使用频率以及在2020年发布的非Cochrane评论中报告RoB2评估的充分性。这项荟萃研究包括2020年发表的干预措施的非Cochrane系统评价。对于使用RoB2工具的评论，我们分析了RoB2评估报告.在3880条评论中，CochraneRoB1工具是最常用的工具(N=2228；57.4%)，其次是CochraneRoB2工具(N=267；6.9%)。从使用RoB2工具报告的267条评论中，213（79.8％）实际使用它。在26条(12.2%)评论中，错误的陈述被用来表明RoB2评估。只有20条（9.4％）评论提出了完整的RoB2评估，并提供了所有信令问题的详细答案表。158条（74.2%）评论中的评论没有证明RoB2工具对偏见风险的判断是合理的。仅在33条（14.5％）的评论中，所有领域的判断在随附的评论中都是合理的。在大多数评论(81.7%)中，研究水平的RoB评估不充分.总之,2020年发布的大多数非Cochrane评论仍使用CochraneRoB1工具。许多评论未充分使用RoB2工具。需要进一步研究RoB2工具的摄取和使用。
