Godfrey K
N Engl J Med. 1985 Dec 5;313(23):1450-6. doi: 10.1056/NEJM198512053132305.
This article discusses statistical methods for comparing the means of several groups and focuses on examples from 50 Original Articles published in the Journal in 1978 and 1979. Although medical authors often present comparisons of the means of several groups, the most common method of analysis, multiple t-tests, is usually a poor choice. Which method of analysis is appropriate depends on what questions the investigators wish to ask. If the investigators want to identify which of the groups under study are different from the rest, they will need a different method from the one required if they wish simply to decide whether or not the groups share a common mean. More complicated questions about the group means call for more sophisticated techniques. Of the 50 Journal articles examined, 27 (54 per cent) used inappropriate statistical methods to analyze the differences between group means. Investigators need to become better acquainted with statistical techniques for making multiple comparisons between group means.
本文讨论了比较多个组均值的统计方法，并重点关注了1978年和1979年发表在该期刊上的50篇原创文章中的示例。尽管医学作者经常呈现多个组均值的比较，但最常用的分析方法——多重t检验，通常并不是一个好的选择。哪种分析方法合适取决于研究者想问的问题。如果研究者想确定所研究的组中哪些与其他组不同，他们将需要一种与只想简单判断这些组是否具有共同均值时所需的方法不同的方法。关于组均值的更复杂问题需要更复杂的技术。在所审查的50篇期刊文章中，有27篇（54%）使用了不恰当的统计方法来分析组均值之间的差异。研究者需要更好地熟悉用于在组均值之间进行多重比较的统计技术。
