A confounding factor is a "hidden" factor or characteristic that may cause an association that the researchers attribute to other factors.

A confounding factor is indeed a hidden variable that can distort the apparent relationship between two or more variables. In research, when investigating the association between a particular exposure and an outcome, confounding factors can introduce bias by creating a false impression of a relationship. For example, if researchers are studying the link between diet and health outcomes, a confounding factor such as physical activity level can influence both diet and health outcomes independently.

By failing to account for these confounding factors, researchers may mistakenly conclude that one variable causes changes in another, when in fact, the relationship may be influenced by these additional hidden factors. Thus, recognizing and controlling for confounders is crucial for yielding valid and reliable research findings. This understanding underscores the importance of careful study design and statistical analysis to discern true relationships from those that are merely products of confounding influences.