PICO, or sometimes PICOT, helps formulate the search strategy by identifying the key concepts that need to be in the article that can answer the question.
How would you describe a group of patients similar to yours? What are the most important characteristics of the patient?
What main intervention are you considering? What do you want to do with this patient?
What is the main alternative being considered, if any?
What are you trying to accomplish, measure, improve or affect?
The T can stand for several different items.
Therapy / Diagnosis / Harm / Prognosis / Prevention
Systematic review / RCT / cohort study / case control
Span of time
From: Sackett, DL. Evidence-based medicine: how to practice and teach EBM.