[The center effect in multicenter studies: fixed or random?].
[The center effect in multicenter studies: fixed or random?].
复制标题
[多中心研究中的中心效应：固定还是随机？]。
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
M. Chavance
中科院分区：
文献类型：
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作者：
B. Falissard;M. Chavance
多中心临床研究的增多导致了在统计分析中中心效应应用的普遍化。在因变量是定量的并且只有一个简单的兴趣因子的简单情况下，这种协议的形式化对应于通常具有交互项的双向方差分析（具有兴趣因子和中心因子）。即使是这样一个简单的情况也会导致审讯，其中之一就是确定中心效应是固定的还是随机的。在第一种情况下，研究的结论将只涉及研究中评估的中心，而在第二种情况下，结论将涉及随机选择中心的整个人口。这种一般化是有代价的：丧失了决定利息因素影响的能力（这种丧失与利息相互作用因素x中心因素一样重要），以及需要复杂的统计软件。本文将依次关注：方差分析的概念，固定效应或随机效应（与区分这两种方法的概念，形式和数值差异）。给出了一个数值算例。
The multiplication of multicentric clinical studies leads to a generalization of the use of a center effect in statistical analyses. In the simple situation where the dependent variable is quantitative and there is only a simple factor of interest, the formalisation of such a protocol corresponds to a two way ANOVA (with the factor of interest and the center factor) with generally a term of interaction. Even such a simple situation leads to interrogations, one of them being to determine whether the centre effect is fixed or random. In the first situation, the conclusion of the study will concern only the centres evaluated in the study, while in the second, the conclusion will concern the whole population from which the centers have been randomly selected. Such a generalizability has a cost: a loss of power in determining the effect of the factor of interest (the loss being as important as the interaction factor of interest x centre factor is large) and the necessity of sophisticated statistical software. This paper will focus on successively: the notion of ANOVA, of fixed or random effect (with the conceptual, formal and numerical differences that distinguish these two approaches). A numerical example is proposed.