Critical Appraisal in Evidence-Based Medicine

Critical Appraisal

• Critical appraisal is the process of carefully and systematically examining research to judge its trustworthiness, value, and relevance in a particular context.
• It is an essential skill for evidence-based medicine, allowing clinicians to find and use research evidence reliably and efficiently.

Critical Appraisal Process

• Critical appraisal involves systematically evaluating clinical research papers to establish: • Does the study address a clearly focused question? • Did the study use valid methods to address this question? • Are the valid results of this study important?
• It also involves assessing the data in published research, applying the rules of evidence, adherence to reporting standards, conclusions, generalizability, and risk-of-bias.

Critical Appraisal Skills

• The Critical Appraisal Skills Program aims to help people develop the necessary skills to make sense of scientific evidence, and has produced appraisal checklists covering validity, results, and relevance.
• Different research questions require different study designs, and the best design for studies evaluating the effectiveness of an intervention or treatment is a randomized controlled trial.

Critical Appraisal Tools

• Systematic reviews, which collect, appraise, and combine evidence, should be used when available.
• Critical appraisal checklists help to appraise the quality of the study design and (for quantitative studies) the risk of bias.
• Critical appraisal tools for cross-sectional studies include the AXIS tool and JBI tools, and the JBI tool for assessing case series.

Purpose of Critical Appraisal

• The purpose of critical appraisal is to determine the scientific merit of a research report and its applicability to clinical decision-making.
• It helps to evaluate a study for the general purpose of understanding current information in areas of practice, or for its application to a particular patient problem.
• Critical appraisal is used to frame a clinical question using the PICO format, directing a search and identifying appropriate research reports.

PICO Format

• The PICO format is used to frame a clinical question, including: • Patient / Population • Intervention • Comparison • Outcome

Importance of Critical Appraisal

• Critical appraisal is necessary to ensure reliable information about what might harm or help us when making healthcare decisions.
• Not all research is good quality, and many studies are biased, leading to false conclusions.
• Critical appraisal helps to determine whether a piece of research has been done properly and that the information it reports is reliable and trustworthy.