Critical Appraisal Tools

“Critical appraisal is the process of carefully and systematically examining research to judge its trustworthiness, and its value and relevance in a particular context,” (Burls, 2009).

Amanda Burls, Director of Postgraduate Programmes in Evidence-Based Health Care, University of Oxford

Bias can be introduced at any point in the research process, from study design to publication, and as such, there are many different forms of bias. (For descriptions and examples of forms of bias, see the University of Oxford’s Biases Archive). Bias or systemic error can lead to inaccurate or incomplete conclusions. Therefore it is imperative to assess possible sources of bias in the research you encounter.

Hundreds of critical appraisal tools (CATs) have been developed to help you do so. Rather than providing a comprehensive list, this guide provides a short list of CATs recommended by expert review groups and health technology assessment organizations. The list is organized by study design.