What do you know about this site or publisher? Does the URL tell you anything?
What do you know about the author?
What do you know about the editor or how things are published?
What are they linking to?
What do other sites say about this one?
What is the purpose of this article? What is your goal or purpose for reading it?
Is this good information? Why or why not?
Was there anything you found that you didn't trust but used to find information you did?
TLDR: The degree of evaluation you should do with new information depends on your goals. Take everything with a grain of salt even if it agrees with you. Ask questions.