On collapsibility and confounding bias in Cox and Aalen regression models
On collapsibility and confounding bias in Cox and Aalen regression models
复制标题
DOI：
10.1007/s10985-013-9242-z
复制
发表时间：
2013-07-01
影响因子：
1.3
通讯作者：
Vansteelandt, Stijn
中科院分区：
文献类型：
--
作者：
Martinussen, Torben;Vansteelandt, Stijn
我们研究的情况是，在测量变量存在混杂的情况下，估计暴露变量对生存时间反应的影响是有意义的。由于生存分析中典型效应测量的不可折叠性或非线性，量化混杂的量变得复杂：无论是否进行调整，生存分析通常会推断出不同程度的不同效应估计值，即使与暴露无关，并且从此不再是暴露与生存时间之间关联的混杂因素。有趣的是，我们表明，与索引 Cox 模型的相应系数不同，索引 Aalen 附加危险模型的暴露系数不受这种不可折叠性的影响，因此对于 Aalen 危险模型可以获得混杂偏差量的简单测量，但对于 Cox 模型则不然。我们认为，由于这种可折叠性，各种其他理想的属性都可以归因于阿伦模型。这项工作概括了 Janes 等人最近的工作。 （生物统计学 11：572-582，2010）。
We study the situation where it is of interest to estimate the effect of an exposure variable on a survival time response in the presence of confounding by measured variables . Quantifying the amount of confounding is complicated by the non-collapsibility or non-linearity of typical effect measures in survival analysis: survival analyses with or without adjustment for typically infer different effect estimands of a different magnitude, even when is not associated with the exposure, and henceforth not a confounder of the association between exposure and survival time. We show that, interestingly, the exposure coefficient indexing the Aalen additive hazards model is not subject to such non-collapsibility, unlike the corresponding coefficient indexing the Cox model, so that simple measures of the amount of confounding bias are obtainable for the Aalen hazards model, but not for the Cox model. We argue that various other desirable properties can be ascribed to the Aalen model as a result of this collapsibility. This work generalizes recent work by Janes et al. (Biostatistics 11:572-582, 2010).