Use the CRAAP test to evaluate and determine the credibility and reliability of a source:
CURRENCY - When was the information published or posted? Has the information been revised or updated? Is the information current or out of date for your topic?
RELEVANCY - Does the information relate to your topic? Who is the intended audience? Is the information at an appropriate level (not too easy or advanced for your needs)?
AUTHORITY - Who is the author, publisher, or source? What are the author's qualifications to write on the topic? Check for contact information and credentials of the author.
ACCURACY - Where does the information come from and is it supported by evidence? Has the information been reviewed and approved (ex: peer-reviewed articles)? How reliable is the information?
PURPOSE - What is the purpose of the information (inform, persuade, sell, or entertain)? Are the intentions of the author clear? What is the intent of the author? Are there political, cultural, institutional, or personal biases?