Video - Confounding

A confounding variable is a variable that distorts the accurate relationship between exposure and the outcome. For example, suppose you're studying the effects of a new drug. In that case, age might be a confounding variable because the drug may affect people of different ages differently. Confounders can make the outcome and exposure look more or less than they are.

There are many ways to control for confounding variables, such as stratifying your data (i.e., dividing your data into subgroups) or using multivariate analysis. However, there is no perfect way to completely eliminate confounding variables, so always be aware of them and try to account for them as best you can.