Before you begin to think critically about the resource at hand, it is important to make sure that it is appropriate for the current need. Also, it is crucial to remember that if a resource, or specific information, is not appropriate in one case, it very well may be useful in a different context.
Do not think about resources and information as "good" or "bad" - information selection and determining it's usefulness is not a black or white, yes or no, process. Make selections based on the current need.
For example, one Think Question asks, "Does the author have an agenda beyond education or information?" If the answer is "yes" - next think, "Am I searching for resources that demonstrate a particular point of view or agenda?" If the answer is no, maybe moving on from this source is the next step. If the answer is yes, maybe investigating further to see if the source truly suits the research need at hand is the next step.
Finding unbiased resources:
Purpose/Point of view of source