Primary, Secondary & Tertiary Sources

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Another way to categorize information is by whether information is in its original format or has been reinterpreted.

Another information category is publication mode, which has to do with whether the information is in its original form, a restatement or interpretation of original information, or something that summarizes original information.

Information may be a:

Primary Source—Information in its original form, which is not translated by anyone else and has not been published elsewhere. Such as:

  • A play
  • A novel
  • Breaking news
  • An advertisement
  • An eyewitness account
  • A painting
  • A report about a scientific discovery

Secondary Source—Repackaged, restatement, or interpretation of primary information. Such as:

  • A book about an historical event
  • An article that critiques a novel, play or painting
  • An article or web site that summarizes and synthesizes several eyewitness accounts for a new understanding of an event.

Tertiary Source—An index or something that condenses or summarizes information. Such as:

  • Almanacs
  • Guide books
  • Survey articles
  • Timelines
  • User guides
  • Encyclopedias

Primary sources include those that can answer your research questions and convince your audience that your answer is the correct one or at least a reasonable one. However, in our discussion of mode, it’s important to recognize that academic disciplines vary in what kinds of sources they consider primary sources. In other words, different disciplines accept different sources as those that can speak with authority—as those that can meet the information needs of answering your research question and convincing your audience your answer is correct or at least reasonable.

For instance, in the humanities, sciences, and social sciences, peer-reviewed scholarly journal articles are considered the most authoritative. But in the arts, it is the art itself—for instance, the painting, the choral performance, the hip-hop dancing done on the street—that speaks most convincingly. That doesn’t mean you could never use a video of a hip-hop dancer in a project for sociology or other social science. But if you did, it would not be to answer your research question or to convince your audience you have the right answer. It would be to meet another information need—for instance, to describe the situation surrounding your research question for your audience or convince them it is important.

If you haven’t been able to tell what sort of sources your instructor considers able to answer your research questions and convince your audience, do ask him or her. It’s an important question, and he or she will probably be impressed that you know enough to ask it.

Activity: Primary, Secondary, or Tertiary?

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