Zhang Zhongheng
Department of Critical Care Medicine, Jinhua Municipal Central Hospital, Jinhua Hospital of Zhejiang University, Jinhua, Zhejiang, People's Republic of China.
BMJ Open. 2015 Jan 16;5(1):e006524. doi: 10.1136/bmjopen-2014-006524.
The present study aimed to combine observational evidence with randomised controlled trials (RCTs) by using the Bayesian approach.
Electronic databases, including PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science, EMBASE and EBSCO were searched from inception to January 2014.
RCTs and observational studies (OS) investigating the effectiveness of activated protein C (aPC) on mortality reduction were included for analysis.
Patients with sepsis.
aPC.
Observational evidence was incorporated into the analysis by using power transformed priors in a Bayesian. Trial sequential analysis was performed to examine changes over time and whether further studies need to be conducted.
a total of 7 RCTs and 12 OS were included for the analysis. There was moderate heterogeneity among included RCTs (I(2)=48.6%, p=0.07). The pooled OR for mortality from RCTs was 1.00 (95% CI 0.84 to 1.19). In OS, there was potential publication bias as indicated by the funnel plot and the pooled OR for mortality with the use of aPC was 0.67 (95% CI 0.62 to 0.72). The pooled effect sizes of RCTs were changed by using different power transform priors derived from observational evidence. When observational evidence was used at its 'face value', the treatment effect of aPC was statistically significant in reducing mortality.
while RCT evidence showed no beneficial effect of aPC on sepsis, observational evidence showed a significant treatment effect of aPC. By using power transform priors in Bayesian model, we explicitly demonstrated how RCT evidence could be changed by observational evidence.
The protocol for the current study was registered in PROSPERO (registration number: CRD42014009562).
本研究旨在通过贝叶斯方法将观察性证据与随机对照试验（RCT）相结合。
检索电子数据库，包括PubMed、Cochrane对照试验中央注册库（CENTRAL）、ISI科学网、EMBASE和EBSCO，检索时间从建库至2014年1月。
纳入调查活化蛋白C（aPC）降低死亡率有效性的随机对照试验和观察性研究（OS）进行分析。
脓毒症患者。
aPC。
在贝叶斯分析中使用幂变换先验将观察性证据纳入分析。进行试验序贯分析以检查随时间的变化以及是否需要开展进一步研究。
共纳入7项随机对照试验和12项观察性研究进行分析。纳入的随机对照试验存在中度异质性（I(2)=48.6%，p=0.07）。随机对照试验中死亡率的合并比值比为1.00（95%可信区间0.84至1.19）。在观察性研究中，漏斗图显示存在潜在发表偏倚，使用aPC时死亡率的合并比值比为0.67（95%可信区间0.62至0.72）。使用源自观察性证据的不同幂变换先验改变了随机对照试验的合并效应量。当按观察性证据的“表面价值”使用时，aPC在降低死亡率方面的治疗效果具有统计学意义。
虽然随机对照试验证据显示aPC对脓毒症无有益作用，但观察性证据显示aPC具有显著治疗效果。通过在贝叶斯模型中使用幂变换先验，我们明确展示了观察性证据如何改变随机对照试验证据。
本研究方案已在国际前瞻性系统评价注册库（PROSPERO）注册（注册号：CRD42014009562）。
