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Radiography, Radiotherapy & Oncology subject guide

A guide to library and information resources for diagnostic and therapeutic radiography students

Evaluating Information

Once you’ve found a piece of information, you will be expected to judge its reliability and suitability to be used in an academic assignment. This page outlines the key things to think about when evaluating information.

This model will help you to assess the quality of an information source that you have found when searching for information. It encourages you to think critically about how reliableaccurateup-to-datevalid and relevant it is in relation to your subject. This will help you decide whether or not to select it to use in your academic studies.

A diagram titled "Evaluating information" that outlines key questions to ask when evaluating sources, shown in orange circles around the title. The key questions read as follows: "What is the resource? e.g. book/article/website..." "Who is the author? e.g. qualified person/organisation" "Why was it written? e.g to inform/persuade? Is there any bias?" "When was it published or last updated?" "Where is the information from? Are there any references?" "How is it relevant? e.g. titled, keywords, abstract, blurb"

Please see our Understanding research and critical appraisal guide for information and guidance in this area.

Evaluating Information questions

What is the resource?

Can you identify the type of resource. This question can be asked on different levels

For example, is it a website or a journal article?  Is it primary research or secondary research?  What type of research is it? (review article. clinical trial, case study etc.)

Who is the author?

Can you identify the person or organisation responsible for writing the work? Are they qualified or expert on the subject? If you don't know who is responsible for the work - can you be sure that it's credible?

Why was is written?

Can you identify the purpose of the work? For example, is it trying to persuade the reader or does it give a unbiased account? Do you have a thorough understanding of the topic if you only study one point of view?

When was it published or last updated?

Is the information still current to the topic you are researching? If the information is not recent, can you rely on it to provide you with up-to-date information? Evidence from the last 5 - 10 years will be the most up-to-date.

Where is the information from?

Does the author make clear where they got the information in their work from? For example, are they presenting original data or have they provided references. If they have not verified their work with sources, can you trust it?

How is it relevant to your assignment?

Does the work address your research topic in-depth? Is it aimed at an appropriate audience e.g. academics? Have you searched across a range of information to determine that this source is the most suitable to select for your work? If you answer no to any of the above, then even if the resource is good quality, it may not be for you.


The CRAAP Test is another handy checklist (and memorable acronym) to use when evaluating a resource. CRAAP stands for Currency, Relevance, Authority, Accuracy, and Purpose and each category offers a series of questions to ask yourself when assessing the credibility of a resource. These are slightly more detailed that those listed in the basic evaluation model above. The CRAAP test was developed by librarians at California State University, Chico and has been adapted for inclusion in the table below:



  - the timeliness of the information

  • When was the information published?
  • Has the information been revised or updated?
  • Does your topic require current information, or will older sources work as well?
  • Do the links work?

  - the appropriateness of the information for your needs

  • Does the information relate to your topic or answer your questions?
  • Who is the intended audience?
  • Is the information at an appropriate level (i.e. not too elementary or advanced for your needs)?
  • Have you looked at a variety of sources before determining this is one you will use?

  - the source of the information

  • Who is the author/publisher/source/sponsor?
  • What are the author's credentials or organisational affiliations?
  • Is the author qualified to write on the topic?
  • Is there contact information, such as a publisher or email address?
  • Are the authors or the website referred to by other trusted sources?
  • Does the URL reveal anything about the author or source? (e.g. .com .org

  - the reliability, truthfulness and correctness of the content

  • Where does the information come from?
  • Is the information supported by evidence?
  • Has the information been reviewed or refereed?
  • Can you verify any of the information in another source or from personal knowledge?
  • Does the language or tone seem unbiased and free of emotion?
  • Are there spelling, grammar or typographical errors?

  - the reason the information exists

  • What is the purpose of the information? Is it to inform, teach, sell, entertain or persuade?
  • Do the authors/sponsors make their intentions/purpose clear?
  • Is the information fact, opinion or propaganda?
  • Does the point of view appear objective and impartial?
  • Are there political, ideological, cultural, religious, institutional or person biases?



flag Remember!

Different criteria may be more or less important depending on your situation.

Remember to look at all the criteria before making a decision.