Statistics for everyone: ch.30 paired mean of two groups

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ch.30 paired mean of two groups

Let’s calculate the samples size for a study comparing paired means. In a word, this means counting the number of samples in a study that conducts paired t-tests.

A study compares the results of a person’s result of drug A to the result of drug B, or the results of applying two treatments to each person’s legs.

I use a lot of studies comparing before and after a procedure, which statistically allows you to perform paired t-tests and is often found in statistical books. However, I often recommend that the statistic method of comparing before and after be used very limitedly.

There may be a misunderstanding in the second entry, which is not the standard deviation of the values of each group, but the ‘standard deviation of the difference values of each pair’.

The same is true not only for sample counting, but also for paired t-tests, so if you understand paired t-test well, you will understand sample size calculations as well.

The result is 24 pairs like this.

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