The Hierarchy of Evidence is a common tool in Evidence Based Medicine to help you recognize the risk of bias in a research article based on the research design and methodology used. It helps you identify a research method with less risk of bias (at the top), but you must use it carefully!
Poor execution of a research type at the top of the pyramid is often just as bad or worse than excellent execution of a research type from the bottom of the pyramid.
Learn the basics of critical appraisal so you can recognize poor execution and quality of ALL types of research.
Evidence Type | Quick Resource Guide |
---|---|
Systematic Reviews or Meta-Analysis | Cochrane, Ovid, PubMed |
Critically-Appraised Topics, Evidence-Based Guidelines, Clinical Evidence | TRIP, Clinical Guidelines |
Critically-Appraised Articles | ACP Journal Club, many journal titled "Evidence-based..." |
Randomized Controlled Trials | Ovid, PubMed, ClinicalTrials.gov |
Cohort Studies | Ovid, PubMed |
Case-Controlled Studies, Case Series / Reports | Ovid, PubMed |
Background Information / Expert Opinion | Books & e-books, editorials, reference materials |
Image credit: Evidence-Based Practice in Health. University of Canberra Library.
Critical appraisal tools are checklists that can help you focus on the important aspects of the research article.
Some tools come with detailed guides on how to appraise specific types of research articles.
Find one that matches the research methodology in the article you are appraising (clinical trial, cohort study, case-series, etc.).
Explore these videos by Dr. Terry Shaneyfelt, an Associate Professor in the Department of Medicine at UAB in Birmingham, Alabama. Or try the information from other creators linked below.
Browse More Biostatistics Videos