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Evaluating Sources: Critical Appraisal

Learn tools you can use to evaluate information.


The second stage to the evaluative process is critical appraisal. This involves a careful examination of the author's arguments and the evidence they provide to support their claims. Even if you are reading an article published in a top academic journal or a book by a leading authority in your field of study, you should start from a position of neutrality and take the approach that the author (whoever they are) must make a case to persuade you of the validity of their arguments.

Ask questions...

  • Do I find the author’s arguments persuasive?​
  • Are the aims of the study clear?​
  • How strong is the evidence supporting the claims?​
  • What are the strengths and weaknesses of the study? ​
  • What are the limitations of study design? Have these been acknowledged? ​
  • What has research by other authors shown?​
  • Do any factors cause me to doubt the validity or reliability of the research? ​

In addition to the facts and analysis offered by the authors, think about the context of their research, the appropriateness and limitations of study design, and any external factors that may impact the relevance or the importance of their approach.   

Look at the bigger picture

When consulting the literature, seek out the different points of view, set them against each other, test them by questioning them, and see how well they stand up when you raise objections and expose them to opposing views by other authors.

Critical appraisal checklists

There are a number of critical appraisal checklists which can help you evaluate particular kinds of studies. Though primarily intended for healthcare clinicians, these checklists are excellent tools for researchers in any discipline  Here are a few examples:





Keep in mind that most studies have imitations and will rarely tick every box. When a study fails to satisfy one or more criteria on a checklist, consider the extent to which this impacts the evidence (if at all).These considerations can inform the critical discussion in your essay. 

Video: Using the CASP checklist for appraisal of qualitative research

This video offers a brief introduction to CASP:
Young, A. (2020) Using the CASP checklist for appraisal of qualitative research. 3 July. Available at:! (Accessed: 14 July 2023)

Introduction to critical appraisal

Cochrane Mental Health (2019) 1. Introduction to critical appraisal. 28 March. Available at: (Accessed: 12 June 2023)

Critical thinking

Critical thinking is the foundation for good academic writing. It should inform every stage of the journey from planning your essay to embarking on your research project to writing the final draft of your paper. Evaluating and critically appraising sources is a key stage in this process,

  • Critical engagement with the idea or topic 
  • Critical appraisal of each piece of evidence we encounter
  • Comparing competing sources of evidence​
  • Developing an argument on the idea or topic informed by our research

Diagram: Monash University (2022) What is critical thinking? Available at: (Accessed: 16 June 2023)