confounding bias

Confounding bias occurs when an outside factor influences both the cause and the effect being studied, making it appear there’s a direct link when there may not be one. For example, if we study whether exercise reduces heart disease but don’t account for diet, diet could be a confounder—people who exercise may also eat healthier, which actually lowers heart disease risk. This bias can lead us to incorrect conclusions about the true relationship between two variables because the confounding factor is influencing both. Recognizing and controlling for confounders is essential for accurate research.