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Evaluate Sources

How to evaluate a source.

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Evaluate Using the 5 W's and How

When choosing a document to support our writing, we must bring a certain amount of skepticism and always be questioning the value of our sources.  Not all sources are created equal and not all sources are worthy to be included in our work.

So how do we know what documents are worthy and valuable and which ones might be questionable in support of our arguments?

We start by:

  • reading like a detective looking for clues to an unsolved crime
  • questioning like a reporter conducting an interview  
  • looking for bias - be suspicious! Bias conveys partiality, favoritism, bigotry, preferences, preconception, and unfairness
  • considering the tone, style, level of information and assumptions made by the author about the reader

Five W's and How

What is a good source? Consider the following:


  • Who is the author?  What credentials does the author have? If an individual author is not named who is the editor or sponsor? If the source is a web site, is there a link to a "home page" to see who is sponsoring the page?


  • What type of document is it?  Is it a primary or secondary document? Is it an opinion, report, research study, news article, popular article, scholarly article, peer-reviewed article, statistical analysis?


  • When was the information published and/or updated?  Is your topic time-sensitive so that you can only use the most updated information or is your topic more historically oriented?


  • Where was the information published? A scholarly journal, popular magazine, encyclopedia, book, website. Is it a known and respected source in the discipline?


  • Why was the document created? What is the author's purpose - to inform, to persuade, to entertain, to share a point of view? Who is the intended audience? If the source is a web site, you can check the domain name for clues (.edu, .org, .com, .mil, .net) to determine what type of page this might be. Is there an "about" or "what is" link from either the information page or the "home page" that outlines the purpose of the pages? Are they trying to sell something?


  • How was it written? Did the author gather data or information;  incorporate in-text citations and a list of references; present supporting pieces of data, sources, citations, quotes, personal experience, a reliable methodology.  If there's not an actual "works cited," are there any internal references to other sources? If yes, what kind of sources are they? Do these sources supplement the information given? If links are provided, do the links work?
Based on your answers to these questions, do you still feel confident in using the source for your research needs? Why or why not?

What to look for

Here are general questions you should ask when evaluating

print sources and websites. 

What to look for in books and periodicals:

  • Currency: What is the publication date of the resource? 
  • Authority: Who is the author and publisher? 
  • Validity/Accuracy: Is the information accurate or valid?
  • Audience: Who was the resource written for? 
  • Point of view (bias): What is the resource's point of view?

What to look for in web sites:

  • Currency: When was the website last updated?
  • Authority: Who is the author or creator?
  • Validity/Accuracy: Is the information accurate or valid?
  • Audience: Who was the website created for?
  • Point of view (bias): What is the website's point of view?

More Info:


Critical Thinking

Graphic for Ultimate Cheatsheet for Critical Thinking

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