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Evidence Based Medicine (EBM)

EBM Books

COM-P Librarian

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Victoria Caine

Overview of EBM

What is Evidence Based Medicine (EBM)?

"A systematic approach to medicine in which doctors and other health care professionals use the best available scientific evidence from clinical research to help make decisions about the care of individual patients. A physician’s clinical experience and the patient’s values and preferences are also important in the process of using the evidence to make decisions."  (Source: National Institutes of Health)

Five A's of EBM

1. Assess

  • A question arises during patient care
  • Review the situation and population
  • Identify knowledge gaps

2. Ask

  • Formulate a clinical question with PICO
  • Determine the type of evidence you're seeking 
    • Primary literature: RCT, cohort study, case control study, etc.
    • Secondary literature (preferred): systematic reviews, meta-analyses, etc.

3. Acquire

  • Develop a search strategy
  • Select databases and resources to search based on topic and evidence type
  • Search for evidence

4. Appraise

  • Examine the quality of the evidence (validity, significance, generalizability, etc.)
  • Synthesize the best available evidence

5. Apply

  • Consider the patient's values and preferences
  • Determine how to best apply the findings to patient care

Hierarchy of Evidence Pyramid

From lowest to highest quality of evidence: 5. Editorials and expert opinions. 4. Case series and case reports. 3. Cohort studies. 2. Randomized controlled trials. 1. Evidence synthesis (Systematic Reviews and Meta-analyses)

Within EBM, the quality of evidence is organized by a hierarchy. It is organized based on the strength and quality of the information assessed. The strongest forms of evidence include systematic reviews and meta-analysis at the top of the pyramid. As you move towards the bottom of the pyramid, evidence becomes more broad and includes things such as observational studies and basic science searching.