A non-parametric procedure for evaluating treatment effect in the meta-analysis of survival data
A non-parametric procedure for evaluating treatment effect in the meta-analysis of survival data
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DOI：
10.1002/sim.1696
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发表时间：
2004-04-15
影响因子：
2
通讯作者：
Koch, GG
中科院分区：
文献类型：
--
作者：
Moodie, PF;Nelson, NA;Koch, GG
本文解决了将独立临床试验的信息结合起来的问题，这些试验比较了两个治疗组的生存分布。当前考虑审查的荟萃分析方法通常不适用于综合已发表（或未发表）参考文献中总结结果的荟萃分析，因为这些方法需要通常未报告的信息。本文提出了使用 log(-log) 生存函数差异（即 log(- log S-2(t))-log(-logS(1)(t)) 作为对比指数来表示独立试验中的乘法治疗对生存的影响的方法。本文通过积分的第二均值定理表明，该对比指数（表示为 theta）可解释为自然对数尺度上的加权平均值 试验中区间 [theta, t] 内的风险比。当试验内比例风险假设成立时，theta 是试验内考虑的区间 k 的常见风险比的比例常数的对数。在这种情况下，在所提出的方法中使用theta作为对比指标的一个重要优点是theta的估计不受随访时间长度的影响。其他常用的指数如 因为比值比、风险比和风险差在比例风险模型下不具有这种不变性，因为它们的估计可能会受到作为技术制品的随访时间长度的影响。因此，所提出的方法消除了生存荟萃分析中经常出现的问题，因为试验不报告相同随访时间长度的生存情况。即使试验内比例风险假设不现实，所提出的方法也具有 能够检验所有研究中两组的生存分布均无乘性治疗效应的全局零假设。讨论了荟萃分析的加权方案，特别是建议基于有效样本量的加权方案用于涉及审查的事件时间数据的荟萃分析。给出了一个说明该方法的医学例子。模拟研究表明该方法在存在以下情况时表现良好 适度审查。版权所有 (C) 2004 John Wiley Sons, Ltd.
This paper addresses the problem of combining information from independent clinical trials which compare survival distributions of two treatment groups. Current meta-analytic methods which take censoring into account are often not feasible for meta-analyses which synthesize summarized results in published (or unpublished) references, as these methods require information usually not reported. The paper presents methodology which uses the log(-log) survival function difference, (i.e. log(- log S-2(t))-log(-logS(1)(t)), as the contrast index to represent the multiplicative treatment effect on survival in independent trials. This article shows by the second mean value theorem for integrals that this contrast index, denoted as theta, is interpretable as a weighted average on a natural logarithmic scale of hazard ratios within the interval [theta, t] in a trial. When the within-trial proportional hazards assumption is true, theta is the logarithm of the proportionality constant for the common hazard ratio for the interval considered k within the trial. In this situation, an important advantage of using theta as a contrast index in the proposed methodology is that the estimation of theta is not affected by length of follow-up time. Other commonly used indices such as the odds ratio, risk ratio and risk differences do not have this invariance property under the proportional hazard model, since their estimation may be affected by length of follow-up time as a technical artefact. Thus, the proposed methodology obviates problems which often occur in survival meta-analysis because trials do not report survival at the same length of follow-up time. Even when the within-trial proportional hazards assumption is not realistic, the proposed methodology has the capability of testing a global null hypothesis of no multiplicative treatment effect on the survival distributions of two groups for all studies. A discussion of weighting schemes for meta-analysis is provided, in particular, a weighting scheme based on effective sample sizes is suggested for the meta-analysis of time-to-event data which involves censoring. A medical example illustrating the methodology is given. A simulation investigation suggested that the methodology performs well in the presence of moderate censoring. Copyright (C) 2004 John Wiley Sons, Ltd.