PICO is a framework used to structure clinical questions, and is the most common model for doing so. It stands for:
P Population: How would you describe the problem or a group of patients similar to yours?
I Intervention: What main intervention, prognostic factor, or exposure are you considering?
C Comparison: Is there an alternative to compare with the intervention?
O Outcome: What do you hope to accomplish, measure, improve, or affect?
From the Medical College of Wisconsin Libraries
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