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The Annotated Bibliography: Step by Step Guide: STEP ONE: Evaluate Sources

This library guide covers everything you need to know about writing an annotated bibliography


It's easy to deliver an A+ annotated bibliography if you follow three main steps. First, as with any research, evaluate your sources to verify credibility and relevance. The second step involves writing your annotation for each source. The final step is to make sure you're writing in the correct style. Let's get started with Step One . . .



You've probably heard "If it's on the Web it must be true!" before. Well, it may not be, and you may find false information on dozens of sites. Here are some tips to be sure that your research is as accurate as possible. The author helps determine credibility. Be wary of websites or documents hiding personal opinion as fact. If the information is not presented as a personal viewpoint, what is the original source? Is the source credible? Any group can give itself an official sounding name or logo.  Fact checking is important. It pays to know who - or what - you are dealing with, both in business and in academics. The best way to evaluate information is through the CRAAP Test. Yes, that's really the name of the useful tool for verifying reliability and validity.



When analyzing text, it's important to consider bias. Bias doesn't necessarily indicate that it should be discarded, but you have to use your own critical thinking skills to evaluate the content. For instance, the author may thank a pro-life organization for supporting research on abortion. You may feel that suggests a biased work, which fails to present facts. A hasty judgment may cost you valuable research. Secondary sources provide interpretations of primary data, and interpretations are influenced by the author's context. Determine where the author stands and use the evidence accordingly. Look at different interpretations of data to help establish your point. Remember--in order to present an effective argument, you should know BOTH sides of the argument!


Does your source apply to your research? If using a book, examine the table of contents to decide. Look at the book's index. You can use the index to look at specific passages and determine whether your topic is well defined. You can read an abstract if your source is online or even skim the article.


You've heard it often-KNOW YOUR AUDIENCE. It's important to consider the intended audience when analyzing text. For instance, if you encounter a work that contains a lot of data and graphs, it's likely that it was aimed at an academic audience. If the rhetoric seems simple and includes pictures, the author may have been aiming for a younger audience. Observe the advertisements if you're evaluating an article in a newspaper or magazine. Who does the publisher seem to be trying to reach?

Checking for Website Credibility

Ask yourself the following questions when researching from a website:

  • Does the information have a complete list of works cited?
  • Are the references credible, authoritative sources?

If the information is not backed up with sources, what is the author's relationship to the subject?

  • Is the expert qualified to give an "expert" opinion?
  • Is the Web information current?
  • If there are a number of nonworking web links or old news, what does this do to the credibility of the information?
  • Is the author biased? Is the author selling or promoting a product?
  • Does the author take a personal stand on an issue?
  • Is the author objective?
  • How does the author qualify as an expert on the topic?
  • Is there contact or sponsorship information?
  • Where was the source published?
  • Is the source a primary or secondary text?

What Kind of Sources Should be Avoided?

  • Popular and collective websites (,,,, etc.) are not generally acceptable as credible sources. These sites have freelance writers who may or may not be experts in the field. The articles and information they collect from other sources may not be reliable. Often, there will not be citations for data sources and if there are, the citations may be from similar sites that do not require expertise in the subject matter.
  • Wikipedia is an online open-source encyclopedia edited by anyone and not fact-checked by experts. Information contained on its pages may not be correct or current. It is not considered, in most cases, to be a valid college-level source.
  • Source material based solely on opinion: Material may or may not be valid, but the material needs reliable sources to support the stated opinions or beliefs with facts and trustworthy information.

Some sources provide a works cited list or reference list. Always check the original source to verify and interpret the information. The sites listed above may not be credible resources in themselves, but may provide links to credible information.

Credible Sources


In order to critically analyze sources, you should ask questions. Examine authors closely. When you select a book or article, ask yourself the following questions:

  • Am I familiar with that author?
  • Is this author cited in other articles or books on the subject he or she is writing about?
  • Have you heard your instructor mention the author's name?
  • Is the author associated with a university?
  • What else has the author written?

Date of Publication

You want the most current sources you can find if you are researching a current issue. If you're researching an older topic, you may go back several years to look at sources. If you're researching something that happened a hundred years ago and there's been a recent article or book written about it, be sure to check it. Perhaps the author found new evidence that changes the first book's argument. Check the translation information. If you see more than one date, a newer edition may reveal new information about the topic.

Evaluating Sources-from Purdue Online Writing Lab


The tone of an article or book reveals how the author represents himself or herself through the text. Impassioned rhetoric may suggest that the author is too emotionally invested to the work to provide a thorough objective analysis. Ask yourself the following questions about the author's tone:

  • Does the author make wild claims or assertions?
  • Does the author use emotional rhetoric?
  • Does the author seem focused on the argument he or she is making?
  • Does the author's thoughts seem random and incomplete?
  • Does the author's information appear to be propaganda?
  • Does the author's rhetoric suggest an objective viewpoint?

Remember, even though an author may appear biased, that does not mean it is bad information. Weigh your options to determine whether it is information relevant to your research.

The Most Important Tool to Evaluating Credibility

YOU! You are the most important tool for evaluating a source's credibility. Use common sense and critical thinking skills to determine an author's credibility. Be vigilant in your research. Remember to consider both sides of an issue if you want to effectively argue a point. You cannot conduct too much research. If you read an article stating that dogs are starting a revolution to usher in a world without cats, common sense tells you the information is not credible. Always use common sense.