When evaluating whether the information in any source is reliable, a few things to consider are:
What does peer-reviewed mean:
When your professor tells you to use peer-reviewed articles or peer-reviewed journals, they want you to use articles from scholarly journals that review submissions before publication. In the peer-review process, an author sends a manuscript of their article to the journal. The journal editor(s) send the manuscript to other experts in the author’s field (i.e. their peers) and ask for comments. Based on the comments, the journal editors either accept the article, reject it, or accept it with conditions. If the article is accepted with conditions, the author can revise it based on the reviewers’ comments and resubmit it. The intent is to ensure quality. Sometimes the term “refereed” Is used in place of “peer-reviewed”.
Is everything in a peer-reviewed journal peer-reviewed:
The articles are peer-reviewed but editorials, letters to the editor, and book reviews are not articles and are not peer-reviewed.
How do I know if a journal is peer-reviewed:
Professional journalists and other fact checkers use the concept of lateral thinking. The Four Movements, or SIFT, spell out what to do: