Statistics IV: Interpreting the results of statistical tests

This is the fourth in a series of articles in this journal on the use of statistics in medicine. In the previous issue, we described how to choose an appropriate statistical test. In this article, we consider this further and discuss how to inter-pret the results. More on choosing an appropriate statistical test Deciding which statistical test to use to analyse a set of data depends on the type of data (inter-val or categorical, paired vs unpaired) being analysed and whether or not the data are nor-mally distributed. Interpretation of the results of statistical analysis relies on an appreciation and consideration of the null hypothesis