While it may seem easier to do a web search for information rather than use a library database, you need to critically evaluate web sites. While there are numerous web pages that describe how to evaluate a web site, here are a few that you may find useful:
If you're looking for statistical information online, be sure that you can trust the source before using it.
One way that you can do this is to limit your results to certain domains:
site:.gov or site:.edu
Many organizations (.org) also collect statistical data. In order to ensure that an organization is legitimate, be sure to check the About Us/Contact Us links to learn more about them.