In regression analysis, what does a mediator variable do?

In regression analysis, a mediator variable plays a crucial role in the relationship between an independent variable and a dependent variable. Specifically, a mediator variable explains the process or mechanism through which the independent variable influences the dependent variable. This means that the presence of a mediator helps to clarify how or why a certain effect occurs.

For instance, if we consider a situation where an independent variable (like a particular treatment) affects a mediator variable (like coping skills), which in turn affects the dependent variable (like patient outcomes), the mediator helps illustrate that the effect of the treatment on outcomes is transmitted through changes in coping skills. This helps researchers understand the underlying mechanisms behind observed relationships in their data.

By focusing on the mediation effect, researchers can gain insights not only about direct relationships but also about the pathways through which those relationships operate, leading to a more nuanced understanding of the phenomena studied.