直接证据来自直接比较我们关注的干预措施用于我们关注的患者人群，并测量患者重要结局的研究。间接证据可由以下4种方式之一产生。第一，患者可能与我们关注的患者不同（适用性一词常用于这类间接性）。第二，所检验的干预措施可能与我们关注的干预措施不同。有关患者和干预措施间接性的决策取决于对生物或社会因素差异是否大到可能使效应尺度出现预期的较大差异的考虑。第三，结果可能有别于最初设定的结局指标——如替代结果本身不重要，但测量之是基于替代结果的变化反映患者重要结局变化这一假设。第四类间接性在概念上与前三类不同，发生于临床医生必须在未经直接比较的两种干预措施间做出选择时。这种情况下比较治疗方案需要特定的统计方法，并根据患者人群、联合干预措施、结局测量指标及备选干预措施试验方法的差异程度，将证据级别降低1或2级。
ObjectiveTo investigate the recommendations on imaging diagnosis in Chinese clinical practice guidelines (CPGs). MethodsWe electronically searched WanFang Data, VIP, CNKI and CBM databases from inception to December 31, 2014. Two reviewers independently screened literature and extracted data. The method of bibliometrics was used to analyze the data (including basic characteristics, strength of recommendation, quality of evidence, etc.). ResultsA total of 341 CPGs formulating the recommendations on diagnosis were included. 48.7% (166/341) guidelines developed the recommendations on imaging diagnosis (a total of 534). 25.7% (137/534) recommendations were with the symbols of quality of evidence and strength of recommendation, and 18.9% (101/534) with special words such as recommend, suggest. 22.3% (119/534) recommendations reported the strength of recommendation. Of which, 38.7% (46/119) were strong and 16.0% (19/119) were weak. However, 23.9% (11/46) strong recommendations were based on low quality of evidence. And 42.1% (8/19) weak recommendations were based on high quality of evidence. ConclusionAmong Chinese CPGs formulating the recommendations on diagnosis, the number of CPGs with recommendations on imaging is about 50%. And the quantity increases by years. The proportions of recommendations on imaging which report the strength of recommendation and/or quality of evidence are low. Meanwhile, the rating systems are uniform. Then the developers do not report the explanation for the strong recommendations based on low quality of evidence or the weak recommendations based on high quality of evidence in guideline.
在GRADE方法中，若多数相关证据来自高偏倚风险的研究，则起初被定为高质量证据的随机试验和低质量证据的观察性研究均有可能被降低质量等级。随机试验已确定的局限性包括：未进行分配隐藏、未实施盲法、未报告失访情况及未恰当考虑意向性治疗原则。最近提出的局限性包括：因明显获益而早期终止试验和基于结果选择性报告结局。观察性研究的主要局限性包括使用不合适的对照及未能充分调整预后的不平衡。偏倚风险可因不同结果而异（如全死因死亡率的失访远少于生命质量的失访），许多系统评价都容易忽略这一点。在决定是否因偏倚风险而降低质量等级时，不管是随机试验还是观察性研究，作者不应采用对各个研究取平均值的方法。相反，对任何单个结果，当同时存在高、低偏倚风险的研究时，则应考虑只纳入较低偏倚风险的研究。
Evidence synthesis serves as a bridge between clinical practice and the best available evidence. Evidence synthesis based on high-quality randomized controlled trials is generally considered the highest level of evidence, but its external validity is limited. In some scenarios, the inclusion of non-randomized intervention studies (NRSI) in evidence synthesis may further supplement or even replace randomized controlled trial evidence, such as assessing intervention effectiveness and rare events in a broader population to provide more information for health care decision-making. With the rapid development of real-world data and the improvement of statistical analysis methods, real-world evidence, as an important source of evidence for NRSI, has accelerated the development of high-quality NRSI. However, there are numerous challenges in integrating evidence from randomized and non-randomized intervention studies due to selection and confounding biases caused by the lack of randomization. Based on previous studies, this paper systematically examines the current status of integrated randomized and non-randomized intervention studies, including integration premise, timing, methods, and result interpretation, in order to provide references for researchers and policy-makers to correctly use non-randomized research evidence and further promote optimal evidence generation and clinical practice translation.
Objective To evaluate the quality of evidence of systematic reviews or meta-analyses regarding outcomes in nursing field in China using the Grade system, so as to get known of the status of the quality of evidence and promote the application of the evaluation of the quality of evidence of systematic reviews. Methods The quality of evidence regarding the included outcomes was input, extracted and qualitatively graded, using GRADEpro 3.6 software. Then, we carefully analyzed and elaborated the factors of downgrading and upgrading that affects the quality of evidence in the process of evaluation. Results 53 systematic reviews or meta-analyses involving 188 outcomes were identified and evaluated. The results showed that high, moderate, low and very low levels of quality of evidence were 2.7%, 27.1%, 51.1%, and 19.1%, respectively; and low-level quality of evidence accounted for the most. Conclusion The quality of evidence produced by systematic reviews or meta-analyses in nursing field in China is poor and urgently needs improvement. The reviewers should abide by the methodological standards in the process of making systematic reviews or meta-analyses. The quality of evidence in terms of each outcome should be evaluated and fully reported.
Previous methods of grading evidence for systematic reviews of diagnostic test accuracy have generally focused on assessing the certainty (quality) of evidence at the level of diagnostic indicators. When the question is not limited to follow the diagnostic test accuracy results themselves, the grading results may be inaccurate due to the lack of consideration of the downstream effects of the test accuracy in specific settings. To address these challenges, the GRADE working group conducted a series of studies focused on updating methods to explore or simulate important downstream effects of diagnostic test accuracy outcomes within a contextual framework. This paper aimed to introduce advances in the contextual framework of the GRADE approach to rate the certainty of evidence from systematic reviews of single diagnostic test accuracy.
In 2014, the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) working group published guidance in BMJ to evaluate the certainty of the evidence (confidence in evidence, quality of evidence) from network meta-analysis. GRADE working group suggested rating the certainty of direct evidence, indirect evidence, and network evidence, respectively. Recently, GRADE working group has published a series of papers to improve and supplement this approach. This paper introduces the frontiers and advancement of GRADE approach to rate the certainty of evidence from network meta-analysis.
ObjectiveTo systematically review the researches on grading criteria for quality of evidence and strength of recommendations of traditional Chinese medicine (TCM). MethodsPubMed, EMbase, Web of Science, CNKI, WanFang Data and VIP databases were electronically searched to collect researches on grading criteria for quality of evidence and strength of recommendations of traditional Chinese medicine from inception to June 2021. Two reviewers independently screened literature, extracted data; and then, descriptive analysis was performed using qualitative methods. ResultsA total of 18 studies were included. Specifically, 8 studies presented both the level of evidence and the strength of recommendations, 9 presented the level of evidence, and 1 presented the strength of recommendations. Thirteen studies considered both TCM evidence and modern medical evidence sources, 3 included only evidence from ancient literature, 1 focused only on post-marketing safety evaluation of Chinese medicine, and 1 focused only on real-world studies of TCM. ConclusionCurrently, there are numerous criteria for TCM related quality of evidence and strength of recommendations, and some are developed only for TCM characteristic evidence. Most researchers of TCM guidelines expect to fully value the significance of ancient literature and expert experience or opinion in guideline development.
GRADE要求明确说明相关的背景、人群、干预措施和对照，同时要求不论研究结果能否形成证据，均需详述所有重要结果。对某一特定管理问题，人群、干预措施及结果应在不同研究间足够类似，才能认为得到相似的效应量合乎情理。指南制定者在收集证据前应先详细说明各结局的相对重要性，同样地，证据总结完成时也需要详细说明这一点。考虑到替代结局的重要性，对采用替代指标描述且对患者很重要的结局，作者应评估其重要性，并进而降低这种间接结果的证据质量等级。
本文是GRADE（Grading of Recommendations Assessment，Development，and Evaluation）系列文章的导论。该系列文章为使用GRADE系统提供指导，介绍如何将该系统用于系统评价、卫生技术评估（HTAs）及临床实践指南中备选方案的证据质量评价和推荐强度评级。GRADE方法始于提出一个明晰的问题，包括对所有重要结果的详细说明。证据被收集和汇总后，GRADE提供了明确的标准来评价其质量，包括研究设计、偏倚风险、不精确性、不一致性、间接性及效应量大小。