Research Center for Genes, Environment and Human Health, College of Public Health, National Taiwan University, Taiwan.
Ann Epidemiol. 2012 Aug;22(8):598-602. doi: 10.1016/j.annepidem.2012.04.017. Epub 2012 May 31.
Microarray technology allows for simultaneously screening many genes and determining which gene(s) are differentially expressed in different disease statuses or different cell types. The analysis of variance (ANOVA) (for a K-sample situation with K>2) can be used in such occasions to gauge statistical significances. However, the test may be underpowered if the diseases under study are heterogeneous.
The authors propose the "control-only ANOVA" for detecting differentially expressed genes in heterogeneous diseases. Monte-Carlo simulation shows that the test produces quite accurate type I error rates for both normal and non-normal data. The statistical power of the control-only ANOVA is higher than that of the conventional ANOVA when the diseases under study are heterogeneous.
Analysis of a real data set shows that after Bonferroni correction, the control-only ANOVA detects three differentially expressed genes, whereas the conventional ANOVA can detect only one.
The control-only ANOVA is recommended for use when the diseases under study are heterogeneous.
微阵列技术允许同时筛选许多基因，并确定在不同疾病状态或不同细胞类型中哪些基因（s）差异表达。方差分析（ANOVA）（对于 K>2 的 K 个样本情况）可用于评估统计显着性。然而，如果研究中的疾病具有异质性，则该检验可能没有足够的功效。
作者提出了“仅对照 ANOVA”，用于检测异质疾病中的差异表达基因。蒙特卡罗模拟表明，该检验对于正态和非正态数据都产生相当准确的 I 型错误率。当研究中的疾病具有异质性时，仅对照 ANOVA 的统计功效高于传统 ANOVA。
对真实数据集的分析表明，经过 Bonferroni 校正后，仅对照 ANOVA 检测到三个差异表达基因，而传统 ANOVA 只能检测到一个。
建议在研究中的疾病具有异质性时使用仅对照 ANOVA。
