In your search for information, you eventually face the challenge of evaluating the resources you have located and selecting those you judge to be most appropriate for your needs. Examine each information source you locate and assess sources using the following criteria:
Your resources need to be recent enough for your topic. If your paper is on a topic like cancer research, you would want the most recent information, but a topic such as World War II could use information written in a broader time range.
Does the information come from an author or organization that has authority to speak on your topic? Has the information been peer-reviewed? (You can use Ulrich's Global Serials Directory to determine if a journal is peer-reviewed). Do they cite their credentials? Be sure there is sufficient documentation to help you determine whether the publication is reliable including footnotes, bibliographies, credits, or quotations.
Who are the intended readers and what is the publication's purpose? There is a difference between a magazine written for the general public and a journal written for professors and experts in the field.
Does this article relate to your topic? What connection can be made between the information that is presented and your thesis? An easy way to check for relevance is by reviewing the Abstract or Summary of the article before downloading the entire article.
Biased sources can be helpful in creating and developing an argument, but make sure you find sources to help you understand the other side as well. Extremely biased sources will often misrepresent information and that can be ineffective to use in your paper.
Websites create an interesting challenge in evaluating credibility and usefulness because no two websites are created the same way. Here are things you want to consider when looking at a website:
The look and feel of the website - Reliable websites usually have a more professional look and feel than personal Web sites.
The URL of your results - The .com, .edu, .gov, .net, and .org all actually mean something and can help you to evaluate the website!
Are there advertisements on the site? - Advertisements can indicate that the information may be less reliable.
Check the links on the page - Broken or incorrect links can mean that no one is taking care of the site and that other information on it may be out-of-date or unreliable.
Check when the page was last updated - Dates when pages were last updated are valuable clues to its currency and accuracy.