PICO is a model used mainly by health practitioners as a way to articulate a clinical question in four parts - Problem/Population/Patient, Intervention, Comparison, and Outcome (PICO). It enables practitioners and students to focus their research and look for a specific answer in the published literature.

After first identifying an information need, the next step in evidence-based practice is to re-frame the problem by posing a clearly stated and searchable question. EBP practitioners use a structure called PICO to advance their thoughts from fuzzy and generalized to crisp and precise. 

PICO is a framework for structuring a clinical question by separating it into four components. Framing the PICO helps you identify some of the keywords you will use in searching databases. 

P = What are the significant characteristics of the patient or the population?

I = What intervention are you considering?

C = Are you considering another intervention as a comparison to the first?

O = What is the desired outcome of the intervention(s)?

Time is sometimes a fifth element of PICO.

(T) = How much time does it take for an intervention to reach an outcome?

See the links below for more information and a couple of short, helpful tutorials.