Peer review
01 // What it is
Peer review is the process where other scientists working in the same field examine a study before it's published, checking the methods, the data, and the conclusions for errors or unsupported claims. It's a filter, not a guarantee — a peer-reviewed study can still turn out to be wrong later, but it means independent experts already checked it for obvious flaws before the public ever saw it.
02 // How a study gets peer reviewed
1. Submission
Researchers submit their completed study to a scientific journal in their field.
2. Expert review
The journal sends it to other scientists (the study's 'peers') who examine the methods and evidence closely.
3. Revisions requested
Reviewers usually ask for changes, more evidence, or a clearer explanation of the methods before accepting it.
4. Publication
Once reviewers are satisfied the study is sound, the journal publishes it for the wider scientific community.
03 // What peer review does and doesn't do
- Peer review catches many errors and unsupported claims, but it doesn't guarantee a study is correct — later research can still overturn or refine peer-reviewed findings.
- A peer-reviewed source is generally more trustworthy than a random website or blog post, because independent experts already scrutinized the methods before publication.
- Peer review happens before publication; replication — other scientists independently repeating the study and getting similar results — is a separate, ongoing check that happens afterward.
04 // Questions people ask
Why does peer review matter in science?
It adds a layer of independent expert scrutiny before a study reaches the public, catching flawed methods, weak evidence, or overstated conclusions that the original researchers might have missed or overlooked.
Does peer review mean a study is definitely correct?
No. Peer review checks that a study's methods and reasoning are sound enough to publish, but science self-corrects over time — later studies, including failed replication attempts, can still challenge or overturn peer-reviewed conclusions.
What's the difference between peer review and replication?
Peer review happens before publication, when other experts check a study's methods and reasoning on paper. Replication happens after publication, when other scientists actually repeat the experiment themselves to see if they get similar results.