An important part of your research is identifying the key sources on your topic. You have to choose which ones are reliable and most relevant to answering the question of your essay or dissertation, and to support your arguments.
Use the CRAAP (Currency, Relevance, Accuracy, Authority, Purpose) test to evaluate the sources you have located, and ask yourself the following questions:
When was the source published or posted? Has it been updated or revised since?
Does your topic require current information? Or will older sources work just as well?
Does the source relate to your topic? Does it answer your question?
Is the information at the appropriate level? Who is the intended audience?
Are you comfortable citing this?
Where does it come from? Is it reliable? Is it supported by evidence?
Has the information been reviewed or refereed?
Does the tone seem biased / unbiased?
Who is the author/publisher of the source?
What are their credentials? Are they qualified to write on the topic?
Is the source trustworthy? Is there contact information? Email address? Publisher?
If it is a website, what is the source? For example: government (.gov), university (.ac), organisation (.org)?
What is the purpose of the information? Is it to inform, or teach, or sell, or promote?
Is it fact, opinion or propaganda?
Does the information appear objective and impartial?
A short video tutorial on evaluating journal articles