Evidence synthesis

Systematic review

A structured review using pre-specified methods to identify and appraise relevant studies.

What it means

Definition

Systematic review. A systematic review is stronger than an informal review when it uses transparent search, selection and appraisal methods. Its reliability still depends on the quality and consistency of included studies.

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 review of weak observational studies cannot automatically create strong causal evidence.