There are seven key criteria to consider when evaluating your sources:
Authority: the credentials of the author(s) and to the publisher of the information.
Who wrote or compiled the information? Who published it and why?
Currency: date of publication and the time period covered by the information.
Is the publication current or historic? Does it matter?
Accuracy: the overall reliability and correctness of the information.
Are the facts and statistics correct and verifiable?
Scope: the completeness of the coverage.
Is the publication comprehensive or selective? What is the focus of the source? Is it relevant to your information need?
Objectivity: the point of view taken in the material.
Is there an obvious bias or does it appear to be relatively objective? Is the author simply providing factual information or expressing an opinion?
Documentation: whether the material cites the sources of the information that is presented.
Do the authors or editors include references or is the information compiled from unknown sources?
Presentation: how the material is organized and supplemented.
Are there good access points such as a table of contents or an index? Are there visual aids to enhance or explain the information?
Is the source popular or scholarly? Which will better fulfill your information need?
Is the source primary or secondary? Which will better fulfill your information need?