What is confounded?

Confounding occurs when the effects of two variables on an outcome cannot be distinguished. It happens when a third variable, called a confounding variable, is related to both the explanatory variable and the response variable in a study. This makes it difficult to determine whether the observed association between two variables is due to the effect of one variable on another, or due to the effect of the confounding variable on both variables.

Confounding can be a serious problem in scientific research because it can lead to incorrect conclusions about the relationship between variables. To avoid confounding, researchers need to carefully design their studies by controlling for potential confounding variables, such as through the use of randomization and blinding techniques, or through statistical methods such as multivariable regression analysis.