On Wed, 2008-08-13 at 19:14 -0700, Mark Home wrote: > Dear All: > > I have a clinical study where I would like to compare the demographic > information for 2 samples in a study. The demographics include both > categorical and continuous variables. I would like to be able to say whether > the demographics are significantly different or not. > > The majority of papers that I have read use multiple techniques to achieve > this (e.g., t-test for the continuous variables and either Fischer exact or > Chi-square for categorical). I wonder whether this might lead to spurious > differences due to multiple significance tests. Is there a better way to do > this? > Hi Mark, Most of these comparisons are uncorrected, as the aim is to demonstrate that the samples come from the same population. Therefore, you aren't worried about making a Type I error, but ignoring a sampling difference that might bias your results.
Jim ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
