It is important to be purposeful about creating a well-built clinical question so that you will be able to find the most relevant results possible. A well-built question will address four important items: Patient or Problem, Intervention, Comparison, and Outcome. To help you remember this, you can use the mnemonic PICO. When you are designing your clinical question, here are some topics to take into consideration.
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 gender, age or race of a patient might be relevant to the diagnosis or treatment of a disease.
I= Intervention:
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? Or what factor may influence the prognosis of the patient - age, co-existing problems, or previous exposure?
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 may not always have a specific comparison.
O= Outcome:
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?
From the University of Maryland Health Sciences and Human Services Library subject guide on Evidence-Based Practice. http://guides.hshsl.umaryland.edu/c.php?g=94009&p=609166.