The Publication Manual of the American Psychological Association, 6th edition, defines a scientific journal as "the repository of the accumulated knowledge of a field" (p. 9).
Journals publish articles to communicate research to the academic community.
Frequently, journal articles are peer-reviewed or refereed. They may also be called scholarly. What does it mean to be peer-reviewed or refereed or scholarly?
A peer-reviewed journal is one that is reviewed by persons who are not members of the editorial board and who are not paid employees of the journal. The reviewers are “peers” of the authors in the sense that they have comparable academic or professional experience and are thus qualified to meaningfully critique the quality of the article. The decision whether or not to publish an article normally depends primarily on the judgment of the reviewers, though the editors arbitrate between - and sometimes override - the reviewers’ decisions. The purpose of a peer review system is to ensure an objective standard of quality in articles accepted for publication, which does not depend merely on the subjective preferences of the editorial staff (as long as the articles are consistent with the goals of the journal).
Refereed is another name for peer-review, as the peers who review the article serve as a sort of referee.
The peer-reviewed (or scholarly) label means, literally, that a panel of independent scholars have recommended the article for publication.
To find peer-reviewed journals, use a database of academic journals such as EBSCOhost's Academic Search Premier.
Journal articles are the best source of information you will find. Journal articles are very different from other kinds of articles. Many library databases will allow you to search for journal articles. However, you need to be able to identify journal articles on sight, that is, by looking at them. Why? Because databases often index every item in a journal, including letters to the editor, editorials, news briefs, etc. As far as the database is concerned, these items qualify as journal articles because they are published within a journal issue.
Some characteristics to look for that can identify a journal article:
In terms of determining if it is a journal article or not, look for a bibliography at the end of the article.
Note: None of this makes a determination whether a given article is considered a research article.