The below chart, created by Denver patent attorney Vanessa Otero, is a good jumping off point when considering the level of information various sources provide as well as where those sources lean politically.
The information in this chart doesn't mean that if you find an article from The Economist (near the top of the chart and near the center), you should use it without evaluating it any further. If you're going to use any piece of information you find online as evidence in your own work, you have a responsibility to examine it closely, no matter where it comes from.
Sometimes it's difficult to tell if the information you're looking at is true. In that case, see if you can confirm the information elsewhere: