Power and sample size calculations for studies involving linear regression
Power and sample size calculations for studies involving linear regression
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DOI：
10.1016/s0197-2456(98)00037-3
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发表时间：
1998-12-01
期刊：
影响因子：
--
通讯作者：
Plummer, WD
中科院分区：
文献类型：
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作者：
Dupont, WD;Plummer, WD
本文介绍了涉及线性回归的研究样本量和功率计算的方法。这些方法适用于旨在检测给定幅度的回归斜率的临床试验或测试两个独立回归线的斜率或截距是否通过给定量不同的研究。研究者可以指定回归线的自变量（x）变量的值，或者在进行研究时在观察上确定它们。在后一种情况下，研究人员必须估计自变量的标准偏差。这项研究为实验和观察性研究设计提供了示例。还讨论了Cohen的多个线性回归模型的功率计算方法，并与本研究的方法进行了对比。我们已经在Internet上发布了一个计算机程序，以执行这些和其他样本量计算（请参阅http://www.mc.vanderbilt.edu/prevmed/psintro.htm）。该程序可以确定具有所需能力的指定替代假设所需的样本量，该假设可以通过给定样本量检测到特定替代假设的功率，或者可以用给定功率和给定功率和可以检测到的特定替代假设样本量。可根据要求提供的特定于上下文的帮助消息可以使用此软件很大程度上不言自明。对照临床试验1998; 19：589-601（c）Elsevier Science Inc. 1998。
This article presents methods for sample size and power calculations for studies involving linear regression. These approaches are applicable to clinical trials designed to detect a regression slope of a given magnitude or to studies that test whether the slopes or intercepts of two independent regression lines differ by a given amount. The investigator may either specify the values of the independent (x) variable(s) of the regression line(s) or determine them observationally when the study is performed. In the latter case, the investigator must estimate the standard deviation(s) of the independent variable(s). This study gives examples using this method for both experimental and observational study designs. Cohen's method of power calculations for multiple linear regression models is also discussed and contrasted with the methods of this study. We have posted a computer program to perform these and other sample size calculations on the Internet (see http: //www.mc.vanderbilt.edu/prevmed/psintro.htm). This program can determine the sample size needed to detect a specified alternative hypothesis with the required power, the power with which a specific alternative hypothesis can be detected with a given sample size, or the specific alternative hypotheses that can be detected with a given power and sample size. Context-specific help messages available on request make the use of this software largely self-explanatory. Controlled Clin Trials 1998;19:589-601 (C) Elsevier Science Inc. 1998.