Peer reviewed
Independent specialists assess a scholarly paper before publication. It is an important quality check, not a guarantee that every conclusion is final.
A reader’s guide
Understanding the Evidence
Good evidence deserves careful reading. This guide offers a clear starting point for judging what a source is, what it can tell us, and where its limits lie.
Systematic review
A structured attempt to find, assess, and synthesize all relevant studies answering a defined question.
Meta-analysis
A statistical method that combines results from multiple suitable studies to estimate an overall effect.
Randomized controlled trial
Participants are assigned by chance to groups so researchers can more confidently test whether an intervention caused a difference.
Government report
A publication issued or commissioned by a government body. It may be an authoritative primary source, but it is not necessarily peer reviewed.
Policy brief
A concise explanation of an issue and possible policy responses, often written for decision-makers.
Correlation vs causation
Correlation means two things vary together. Causation means one produces change in the other; stronger evidence is needed to establish it.
Open access
The full work can be read online without a subscription or payment barrier. Open access describes availability, not automatically quality.
Before drawing a conclusion, ask: Who produced this? How was the information gathered? Who was included or excluded? Is the full method available? Are limitations stated? Has another study found something similar? Evidence is strongest when transparency, sound methods, and multiple sources meet.