A confounding variable is an outside influence that can affect the results of an experiment or study. It can create a false impression of a relationship between the independent variable (the one being manipulated) and the dependent variable (the one being measured). For example, if researchers are studying the effect of exercise on weight loss, a confounding variable could be diet, which also influences weight loss. Identifying and controlling for confounding variables is crucial for accurate research outcomes. If not accounted for, these variables can lead to incorrect conclusions, making it difficult to determine whether the observed effects are truly due to the independent variable or influenced by other factors.