**So you want to test if the mean of a numeric outcome differs across more than two groups. Question: Are your measurements repeated or independent?**

You have repeated measures data if every subject in your sample has a measurement under more than two different conditions. Each set of measurements will be related because the were obtained from the same subject.

Examples:

- You measure peoples’ cholesterol before taking a drug, after 6 month, and after 1 year.
- You compare peoples’ ratings of the economy in 2000, 2005, 2010, and 2015.

You have independent measurements when more than two different groups of sample subjects are present, and each subject has a signal measurement under one condition only.

Examples:

- You want to see if students living in dorms, off campus, or with their parents spend the same amount of money on food each week.
- In a drug trial, you give one group of patients a low dose of the drug, one group a high dose, and another group a placebo.