Statistics and risk

Intention-to-treat analysis

An analysis that keeps participants in their originally assigned groups.

What it means

Definition

Intention-to-treat analysis. Intention-to-treat analysis preserves the benefits of randomisation and reflects real-world adherence problems. It can dilute treatment effects but reduces bias from excluding participants after assignment.

What it can tell you

It can help clarify what sort of evidence or claim is being discussed.

What it cannot tell you

It cannot, by itself, prove that the headline is accurate or clinically important.

Headline trap

Why this matters in headlines

A trial result may be more reliable when the main analysis follows intention-to-treat principles.