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Evidence Based Medicine

What is EBM and how does it work?

Evidence Pyramid

The second step in the EBP process is Acquire, to identify and search for the most appropriate information sources that address the question. Remember, practicing EBM is integrating the best research evidence with clinical expertise and patients' circumstances and values. But with the proliferation of information sources and research studies out there, knowing how to find the best evidence can be daunting. Using an evidence pyramid or hierarchy of evidence can help guide the search process.

Evidence Pyramid

The evidence pyramid is a visual representation of the quality and amount of information you might find for any given question. The quality of information increases as you go up the pyramid, but the amount of information decreases. You may not always find a meta-analysis or systematic review on your topic, in which case you would go down and look for the next best level of evidence on the pyramid. Also, the top levels of information are comprised of sources from the lower levels.

There are many evidence pyramids. The pyramid above was designed based on the following sources:

Self-Directed Learning Resources

The Medical Library has compiled a list of Self-Directed Learning Resources that reflect the categories of evidence found on the pyramid. These include subscribed resources made available by the Medical Library as well as a few free resources found on the Web. 

Further Reading