Meta-analysis
A study that combines results from many previous research papers to draw larger, more reliable conclusions about a topic.
A systematic research method that pools data and findings from multiple independent studies on the same question to identify overall patterns, strengthen evidence, and reach more robust conclusions than any single study could provide. Meta-analyses are commonly used in medicine, psychology, and social science to synthesize large bodies of research.
What this means in real life
A researcher wanting to know if a new headache medication works might combine results from 50 different clinical trials involving thousands of patients, rather than relying on one small trial, to get a clearer picture of whether it actually helps.
What it isn’t
It is not a literature review that simply summarizes what other studies found. A meta-analysis uses statistical methods to quantitatively combine data across studies, whereas a review may be qualitative and narrative.
Commonly misused online
People often cite 'a meta-analysis says X' as if it's automatically the final truth, when in reality the quality and scope of included studies, and how they're weighted, can significantly shape the conclusion.