The PICO framework is commonly used to structure questions related to patient therapy. The framework helps to break up the research question into distinct ideas that can be turned into search terms. It identifies the population or patient type being researched and the intervention or exposure used. The comparison component is optional; if used, it names the alternative intervention or therapy. The outcome component of the question is not necessarily included in the search, but it is used to make sure that the search results are relevant to the research question.
You may also see the PEO (Patient/Exposure/Outcome) framework used to frame questions that relate to prognosis, harm, and etiology.
Each type of question can best be answered by certain study methodologies; use the chart below to determine the best type of study to consult for your clinical questions.