Evaluating sources

As you research your Extended Essay, you will explore a range of primary and secondary sources. It's good to collect a lot of sources. But like so many things in life, what you exclude from your essay is just as important as what you include. Filtering, organising and evaluating sources are essential steps in doing research. So what constitutes a valuable source? Below are two methods to help you determine what to include and exclude from your essay. 

CRAP sources

This popular method for evaluating source comes with a snappy acronym and many variations on it. In brief in asks you to look at these 4 aspects of any source: 

Currency: How up to date is your source?
Relevance*: How relevant and is your source to your research question?
Academic authority: Is there a sense of expertise?
Purpose and bias: What is the aim of the source?

*Note: The 'R' in the CRAP method traditionally stands for 'reliability', which arguably overlaps with 'authority'. 'Relevance' plays an equally important role, especially in relation to the Extended Essay.

Examiners will study bibliographies to see if they pass the CRAP test. Click on the slides below to see how several bibliographical entries have been annotated using the CRAP method by an experienced IB workshop leader, John Royce. Try annotating a few sources from your bibliography, using this method. 

7 critical questions to evaluate a source

To evaluate a source is to ask several critical questions of it. These questions are essentially variations of the CRAP method above, with more detail. You can substitue the word 'text' for 'source' if that is more appropriate for the context of your research.

  1. Why am I reading this text?

    • What do I hope to gain by reading this text?

  2. What type of text is this?

    • What kind of audience is targeted by this text?

    • How could this text be classified? Prose?Fiction? Instruction? Expository?

    • Where is the text published?

  3. What are the aims of the author?

    • What is the author's purpose?

    • Is it to inform, persuade or entertain?

    • How as the author approached the topic?

  4. What is being claimed?

    • What is the author's stance on a topic?

    • What values are expressed?

    • How clear are the author's claims?

    • How consistent are the author's claims with other people's claims?

  5. What concepts are key to understanding this text?

    • How do the author's ideas fit into a conceptual framework for this topic?

    • How are various phenomena explained?

  6. What can I take away from this text?

    • What questions, illustrations or diagrams can be used to support my own arguments or ideas?

  7. What is the value of this text?

    • How important is this text to me and to others?

    • How does this contribute to its field or subject area?

    • How does it compare to other texts I've read?


Evaluating your sources critically can help you earn marks on Criterion C: Critical thinking. In fact you are assessed on your ability to 'evaluate the research'. This is to say that you should call into question both your methods, sources and arguments and other people's methods, sources and arguments.

Last modified: Friday, 29 May 2020, 10:34 AM