Institute of Integrated Traditional Chinese and Western Medicine, Chinese Evidence-based Medicine Center, and MAGIC China Center, West China Hospital, Sichuan University, Chengdu, China.
NMPA Key Laboratory for Real World Data Research and Evaluation in Hainan, West China Hospital, Sichuan University, Chengdu, China.
BMJ Open. 2023 Jul 26;13(7):e073232. doi: 10.1136/bmjopen-2023-073232.
Although interest in including non-randomised studies of interventions (NRSIs) in meta-analysis of randomised controlled trials (RCTs) is growing, estimates of effectiveness obtained from NRSIs are vulnerable to greater bias than RCTs. The objectives of this study are to: (1) explore how NRSIs can be integrated into a meta-analysis of RCTs; (2) assess concordance of the evidence from non-randomised and randomised trials and explore factors associated with agreement; and (3) investigate the impact on estimates of pooled bodies of evidence when NRSIs are included.
We will conduct a systematic survey of 210 systematic reviews that include both RCTs and NRSIs, published from 2017 to 2022. We will randomly select reviews, stratified in a 1:1 ratio by Core vs non-Core clinical journals, as defined by the National Library of Medicine. Teams of paired reviewers will independently determine eligibility and abstract data using standardised, pilot-tested forms. The concordance of the evidence will be assessed by exploring agreement in the relative effect reported by NRSIs and RCT addressing the same clinical question, defined as similarity of the population, intervention/exposure, control and outcomes. We will conduct univariable and multivariable logistic regression analyses to examine the association of prespecified study characteristics with agreement in the estimates between NRSIs and RCTs. We will calculate the ratio of the relative effect estimate from NRSIs over that from RCTs, along with the corresponding 95% CI. We will use a bias-corrected meta-analysis model to investigate the influence on pooled estimates when NRSIs are included in the evidence synthesis.
Ethics approval is not required. The findings of this study will be disseminated through peer-reviewed publications, conference presentations and condensed summaries for clinicians, health policymakers and guideline developers regarding the design, conduct, analysis, and interpretation of meta-analysis that integrate RCTs and NRSIs.
尽管人们对将干预措施的非随机研究（NRSIs）纳入随机对照试验（RCTs）的荟萃分析越来越感兴趣，但从 NRSIs 中获得的效果估计比 RCTs 更容易受到更大的偏差影响。本研究的目的是：（1）探讨如何将 NRSIs 纳入 RCT 的荟萃分析；（2）评估非随机和随机试验证据的一致性，并探讨与一致性相关的因素；（3）研究纳入 NRSIs 对汇总证据的估计值的影响。
我们将对 2017 年至 2022 年期间发表的 210 项包含 RCT 和 NRSIs 的系统综述进行系统调查。我们将随机选择综述，并按照美国国立医学图书馆定义的核心和非核心临床期刊进行 1:1 分层。由配对审查员团队使用标准化、经过试验的表格独立确定合格性并提取数据。通过探索 NRSIs 和 RCT 报告的相对效果的一致性来评估证据的一致性，定义为研究人群、干预/暴露、对照和结局的相似性。我们将进行单变量和多变量逻辑回归分析，以检查特定研究特征与 NRSIs 和 RCT 之间估计值一致性的关联。我们将计算 NRSIs 的相对效果估计值与 RCT 的相对效果估计值之比，以及相应的 95%置信区间。我们将使用偏倚校正的荟萃分析模型来研究纳入 NRSIs 对汇总估计值的影响。
不需要伦理批准。本研究的结果将通过同行评审的出版物、会议演讲和针对临床医生、卫生政策制定者和指南制定者的简要总结进行传播，内容涉及纳入 RCT 和 NRSIs 的荟萃分析的设计、进行、分析和解释。
