What is the hierarchy of evidence and how should you use it?
The hierarchy of evidence is a tool that allows you to understand the quality of the information you are viewing. Importantly, a hierarchy assumes that each level builds on the previous. This means that all levels are important, even if they should be used differently. This post goes over each level, and provides an example of what this might look like.
In general, as you go up the pyramid, the number of subjects goes up, the amount of statistical analysis increases, and the amount of bias is reduced.
Always consider that while the lower levels of evidence should not be used to draw conclusions, they are still fundamental to guiding research and should always be recognized. Also remember that as often as you can, draw your conclusions from the highest level evidence available. Of course, each level takes more time to complete so a systematic review or meta analysis may not always be available if a research question is new.
Levels:
1. Patient Reports and Anecdotes
2. Expert Opinion
3. Case Reports and Control Studies
4. Cohort Studies
5. Randomized Controlled Trials
6. Systematic Reviews
7. Meta Analyses
Posted on Instagram on May 25, 2021.