The Well-Built Clinical Question
EBM always begins and ends with the patient. To begin this process, consider the following clinical scenario:
The next step in this process is to take the identified problem and construct a question that is relevant to the case and is phrased in such a way as to facilitate finding an answer.
Anatomy of a good clinical question: PICO
PICO is a mnemonic that helps one remember the key components of a well focused question. The question needs to identify the key problem of the patient, what treatment you are considering for the patient, what alternative treatment is being considered (if any) and what is the outcome you want to avoid or promote.
P = Patient or problem
How would you describe a group of patients similar to yours? What are the most important characteristics of the patient? This may include the primary problem, disease, or co-existing conditions. Sometimes the sex, age or race of a patient might be relevant to the diagnosis or treatment of a disease.
I = Intervention, prognostic factor, or exposure
Which main intervention, prognostic factor, or exposure are you considering? What do you want to do for the patient? Prescribe a drug? Order a test? Order surgery? What factor may influence the prognosis of the patient? Age? Co-existing problems? Has the patient been exposed to something? Asbestos? Cigarette smoke?
C = Comparison
What is the main alternative to compare with the intervention? Are you trying to decide between two drugs, a drug and no medication or placebo, or two diagnostic tests? Your clinical question does not always need a specific comparison.
O = Outcomes
What can you hope to accomplish, measure, improve or affect? What are you trying to do for the patient? Relieve or eliminate the symptoms? Reduce the number of adverse events? Improve function or test scores?
The structure of the PICO might look like this:
Revised July 2010