What is a "confounding variable"?

A confounding variable is defined as an outside influence that has the potential to affect both the independent variable and the dependent variable in a study. When such a variable is present, it can create a false association between the primary variables, leading to skewed or misleading results. For instance, if researchers are examining the effect of exercise on weight loss, a confounding variable might be dietary habits; if not controlled for, it may appear that exercise alone is responsible for changes in weight when, in fact, diet plays a significant role as well.

By identifying and controlling for confounding variables, researchers can isolate the effects of the independent variable on the dependent variable more accurately, thus improving the validity of the study's conclusions. This concept is critical in both experimental and observational research to ensure that findings reflect the true relationship being studied rather than being influenced by external factors.