Critical appraisal

What is critical appraisal?

Critical appraisal involves critically examining a study to determine its validity, reliability and relevance. It is an important and essential part of the EBP 5 step process. For a more comprehensive overview refer to the Critical appraisal for health guide.

It is useful to ask the following three questions when conducting an appraisal:

Are the results of the study valid?
Are the results of the study reliable?
Are the results applicable to my situation? (Saewert & Hagler, 2015¹).

There are many different appraisal tools that can be used depending on the type of study. See below for some examples.

Critical appraisal tools & guides

There are a number of checklists / tools available to assist in the critical appraisal of evidence.

CASP checklists
This set of eight critical appraisal tools are designed to be used when reading research, these include tools for Systematic Reviews, Randomised Controlled Trials, Cohort Studies etc.
Centre for Evidence Based Medicine
University of Oxford - contains useful tools and worksheets for the critical appraisal of different types of medical evidence.
PEDro Scale
Explains why each item has been included in the PEDro scale.
PRISMA
Systematic reviews & meta-analyses. Includes links to PRISMA flow diagram and checklist.

1. Saewert, K. J., & Hagler, D. (2015). Generating the evidence for health professional education: The five As of the scholarship of learning and teaching - ask, answer, access, appraise and apply. In T. Brown & B. Williams (Eds.), Evidence-based education in the health professions: Promoting best practice in the learning and teaching of students (pp. 67-80). London: Radcliffe.