What is the Difference Between Moderator and Mediator?

The main difference between a moderator and a mediator lies in the way they affect the relationship between variables. Here are the key distinctions:

• Mediator: A mediator explains the process through which two variables are related. It lies on the causal pathway between an independent variable (X) and a dependent variable (Y), such that the independent variable is causally associated with the mediator, which, in turn, is causally associated with the dependent variable. A mediator helps to identify the mechanisms that determine which treatments do or do not work.
• Moderator: A moderator affects the strength and direction of the relationship between two variables (X and Y). It does not form part of the causal chain linking X and Y but instead influences the relationship between them. Moderators help to determine the context (under what circumstances, or for what types of people) in which an effect exists or does not and in what magnitude.

In summary, a mediator explains how and why an effect occurs, while a moderator identifies under which conditions an effect occurs. Both mediators and moderators are important to consider when studying complex correlational or causal relationships, as they provide a deeper understanding of the underlying mechanisms and contexts in which relationships between variables exist.

Comparative Table: Moderator vs Mediator

Here is a table summarizing the differences between a moderator and a mediator in research:

In summary, a moderator variable affects the strength and direction of the relationship between two other variables, while a mediator variable explains the process through which two variables are related, including the causal relationship between them.