What is a Confounder?
Confounder (also called Confounding variable) is one of those statistical terms that confuses a lot of people. Not because it represents a confusing concept, but because of how it’s used. (Well, it’s a bit of a confusing concept, but that’s not the worst part).
First, it has slightly different meanings to different types of researchers. The definition is essentially the same, but the research context can have specific implications for how that definition plays out.
If the person you’re talking to has a different understanding of what it means, you’re going to have a confusing conversation.
Let’s take a look at some examples to unpack this.