Who wrote the information? Try checking "about" or "about this site" if the page you're looking at isn't credited. Be wary of anonymous or uncredited information.
What are the author's qualifications and experience? Is there a reason that you should trust the author's information on this topic? Is the author affiliated with a reputable institution or organization?
It may be helpful to look up the author elsewhere to verify his or her qualifications - remember that anyone can claim to be anything. Try searching for the the author's name on the websites of organizations he or she claims to be affiliated with. What do you find there? What do you find if you do a general Internet search on the author's name?