Evaluating Sources

It’s easy to assume that huge amounts of available information automatically provide knowledge. Some students might at first be excited about receiving 20,800,000 hits from a Google search on political ethics, but shock takes hold when they realize that their discovery is utterly unsorted. They might respond by using only the first several hits, irrespective of quality. A more productive approach is to think critically about the usefulness of potential sources by measuring them against three important criteria: relevance, authority, and bias.


The first thing to consider when looking at a possible source is how well it fits your needs. That, in turn, will be affected by the nature of your research project and the kind of information you are seeking.

  • Is it introductory? Introductory information is basic and elementary. It neither assumes nor requires prior knowledge about the topic. Introductory sources can be useful when you’re first learning about a subject. They are less useful when you’re drawing conclusions about a particular aspect of the subject.

  • Is it definitional? Definitional information provides some descriptive details about a subject. It might help you introduce a topic to others or clarify the focus of your investigation.

  • Is it analytical? Analytical information supplies and interprets data about origins, behaviors, differences, and uses. In most cases, it’s the kind of information that you want.

  • Is it comprehensive? The more detail, the better. Avoid unsubstantiated opinions and look instead for sources that consider the topic in depth and offer plenty of evidence to support their conclusions.

  • Is it current? You should usually give preference to recent sources, although older ones can sometimes be useful (i.e., primary sources for a historical topic or if the source is still cited by others in a field).

  • Can you conclude anything from it? Use the “So what?” test: How important is this information? Why does it matter to my project?


Once you have determined that a source is relevant to your project, check that it was created by somebody who has the qualifications to write or speak on the subject. Such checking will depend on your subject and the nature of your inquiry (a fifth grader’s opinion might be exactly what you’re looking for). In most cases, though, you’ll want expert conclusions based on rigorous evidence.

Make sure that you can identify the author and be ready to explain why that author is a reliable source. Good qualifications might include academic degrees, institutional affiliations, an established record of researching and publishing on a topic, and personal experience with a subject. on the other hand, be wary of anonymous or commercial sources or those written by someone whose credibility is questionable.

Also understand whether your project calls for scholarly publications, popular magazines, or both. You don’t necessarily have to dismiss popular magazines. Many journalists and columnists are extremely well qualified, and their work might well be appropriate for your needs. Also, independent and small-press magazines offer perspectives from groups of people who are not often represented in mainstream media outlets. As a general rule, however, scholarly sources will have been vetted through a rigorous process that gives the work credibility in academic environments.

Scholarly Journals Popular Magazines
Long articles Shorter articles
In-depth information on topic Broad overview of topic
Written by academic experts Written by journalists or reporters
Graphs, tables, and charts Photos of people and events
Articles “refereed” or reviewed by experts Articles not rigidly evaluated
Formally credited sources Sources credited informally


When you are searching for sources, you should realize that all materials have an author who has personal beliefs that affect the way he or she views the world and approaches a topic. This bias is a normal part of the research process, and researchers have adopted methodologies to reduce it and improve accuracy. Many sources, however, will be heavily biased toward a specific viewpoint or ideology. Although nothing is inherently wrong with someone having a particular point of view, it is dangerous for a reader not to know that the bias exists.

Research consists of considering multiple analyses, opinions, points of views, and perspectives on a topic; analyzing the sources; and creating something new from your analysis. Some signs of bias indicate that you should question the credibility and accuracy of a source and possibly exclude it from your research. If you detect overly positive or overly harsh language, hints of a personal agenda, or a stubborn refusal to consider other points of view, think carefully about how well you can trust the information in a document.

A Note on Internet Sources

Be especially careful when evaluating online resources. It is often difficult to tell where something on the Internet came from or who wrote it. The lack of this information can make it very difficult to judge the credibility of the source. Although an editorial board reviews most print matter (books, articles, etc.) for accuracy and overall quality, it’s frequently difficult to confirm that the same is true for information on a Web site. There are some exceptions, however. If you are searching through an online database such as the Human Genome Database or Eldis: The Gateway to Development Information (a poverty database), it is highly likely that the documents in these collections have been reviewed. Likewise, online versions of print magazines and journals have usually been checked out by editors. And information from academic and government Web sites (those whose URLs end in .edu or .gov, respectively) is generally—but not always—trustworthy.