The presence of several of the following traits often indicates that an article is peer-reviewed:
A lot of citations: these may appear in-text, and/or as footnotes, endnotes, works cited, reference list, bibliography
An Abstract (brief description of the article) The organization of the article into discrete sections such as Methodology, Results, and Conclusion.
Charts, tables, or graphs
Complex, formal language that is specific to the field
Notes indicating when article was submitted and when it was accepted
If you want to be certain that the journal in which the article appears is peer-reviewed, you can explore the Homepage of the journal on the Internet. Peer-reviewed journals are usually proud to announce that they are peer-reviewed.
Can databases help me identify peer-reviewed articles?
Some databases allow you to select for "peer-reviewed" results only. This can be very helpful, but beware: not all these results will be ARTICLES or peer-reviewed. Some will be book reviews and editorials, and these are not subjected to the same level of critique.