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AÂ repeated measures ANOVAÂ is used to determine whether or not there is a statistically significant difference between the means of three or more groups in which the same subjects show up in each group.

This tutorial explains how to conduct a one-way repeated measures ANOVA in Excel.

**Example: Repeated Measures ANOVA in Excel**

Researchers want to know if four different drugs lead to different reaction times. To test this, they measure the reaction time of five patients on the four different drugs. Since each patient is measured on each of the four drugs, we will use a repeated measures ANOVA to determine if the mean reaction time differs between drugs.

Perform the following steps to conduct the repeated measures ANOVA in Excel.

**Step 1: Enter the data.**

Enter the following data, which shows the response time (in seconds) of five patients on the four drugs:

**Step 2: Perform the repeated measures ANOVA.**

To perform the repeated measures ANOVA, go to theÂ **Data**Â tab and click onÂ **Data Analysis**.Â If you donâ€™t see this option, then you need to firstÂ install the free Analysis ToolPak.

Once you click onÂ **Data Analysis,**Â a new window will pop up. SelectÂ **Anova: Two-Factor Without ReplicationÂ **and click OK.

Note:Â

The Analysis Toolpak doesnâ€™t have an explicit function to perform a repeated measures ANOVA, but theÂ

Anova: Two-Factor Without ReplicationÂwill produce the results weâ€™re looking for, as weâ€™ll see in the output.

ForÂ **Input Range**, type in the cell range that contains the response times for the patients. Feel free to leaveÂ **AlphaÂ **at 0.05, unless you wish to use a different significance level. ForÂ **Output Range**, choose a cell where you would like the results to appear. Then clickÂ **OK**.

The results will automatically appear:

In this case we are not interested in the results for the Rows, only for the Columns, which tell us the variation in response time based on the drug.

The F test-statistic isÂ **24.75887Â **and the corresponding p-value isÂ **0.0000199**. Since this p-value is less than 0.05, we reject the null hypothesis and conclude that there is a statistically significant difference in mean response times between the four drugs.

**Step 3: Report the results.**

Lastly, we will report the results of our repeated measures ANOVA. Here is an example of how to do so:

A one-way repeated measures ANOVA was conducted on 5 individuals to examine the effect that four different drugs had on response time.

Â

Results showed that the type of drug used lead to statistically significant differences in response time (F(3, 12) = 24.75887, p