Collider bias and the problem with vaccine case-control studies

How the bias can lead to the wrong conclusions about treatment effectiveness

Before we go into vaccine case control studies the bias issue at hand is pretty easy to understand and it might surprise you to learn that you have probably already encountered it in everyday life, from dating and when forming friendships.

Why do we believe ‘attractive’ people are more likely to be ‘mean’ than ‘nice’?

Let’s assume for simplicity that you …