Articles in journals have already been published, and have gone through a review and editing process, unlike web sites. But it is still a good idea to look at the information critically.
Source - Look for articles from scholarly journals, written by experts in the subject. There will be references that can lead you to additional books and articles on the topic. In some databases, you can limit your search by type of article -- a research article, an editorial, a review, or a clinical trial.
Length - The length of the article, noted in the citation, can be a good clue as to whether the article will be useful for research.
Authority - Use authoritative sources in your research. Use articles written by experts in the subject area, and who are affiliated with an academic institution.
Date – research in many subjects requires the most current information available. Is the article sufficiently up-to-date for your purpose?
Audience - For what type of reader is the author writing? If an article is written for other professionals, it will use terms and language special to the subject area.
Usefulness - Is the article relevant to your research topic?