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What is PICO?

A well-built clinical question helps you begin searching for evidence-based answers. Good clinical questions can be built using the acronym PICO.

P - Patient, population or problem of interest

I - Intervention - therapy, diagnostic test, exposure, etc.

C - Comparison intervention (can be blank if no treatment is the comparison)

O - Outcome(s) of interest

For example, you may wish to answer, "What is the best way to prevent infection through hand-to-hand contact in the hospital - alcohol-based hand sanitizers or traditional hand washing?"  "Best" is subjective - so restate your question in the PICO format to get a clinical answer.

  • P - Hospitalized patients
  • I - Use of alcohol-based hand sanitizers
  • C - Traditional hand washing 
  • O - Control infection

Using PICO will help you translate your question from an initial broad topic or a specific individual patient's experience, to a concrete objective question that you can look to find clinical evidence to answer. Use words from your PICO question to build a search string. The search string is a list of words you will enter into the research databases to help you find articles.

Using the example above, our search string could be: "alcohol-based hand sanitizers" AND "hand washing" AND infection AND "systematic review" 

The Centre for Evidence Based Medicine has tips and practice examples for formulating research questions.

A list of other Evidence-Based Modules and Tutorials.

The Five Steps of Evidence-Based Practice

Step 1: Convert the need for information into an answerable question (using PICO - see the "What is PICO?" box to the right)

Step 2: Find the best evidence (from Systematic Reviews) to answer that question (using Library and public domain databases from the web)
                 Tip: Systematic Reviews are articles that find, evaluate, and summarize several
                 research studies in one article.

Step 3: Critically appraise the evidence for its validity, impact, and applicability

Step 4: Integrate the evidence with your clinical expertise and the patient's unique biology, values and circumstances

Step 5: Evaluate the effectiveness and efficiency of the process

Strauss, S. E. (2005). Evidence-based medicine : How to practice and teach EBM (3rd ed.). New York: Elsevier/Churchill Livingstone

Documents Useful for EBP