what is a confounding variable
A confounding variable is an extraneous variable that is related to your independent variable and might affect your dependent variable. In an ideal study, there will be no confounding variables. Let's look at another example of a confounding variable; let's say that whenever Josh is stressed out, he gets muscle cramps. He thinks that stress causes his muscle cramps. In this example, stress is the independent variable, and the muscle cramps are the dependent variable.
University of Michigan School of Public Health. University of Michigan School of Public Health Office of Public Health Practice. Definition: A confounder is a third variable that can make it appear (sometimes incorrectly) that an observed exposure is associated with an outcome. In other words, a confounder is an unobserved exposure associated with the exposure of interest and is a potential cause of the outcome of interest.