The PICO model is used in medicine to form a well-built clinical question that can be used to form a search strategy when doing research.
PICO is a mnemonic used to describe the four elements of a good clinical foreground question.
P = Population/Problem
How would I describe the problem or a group of patients similar to mine?
I = Intervention
What main intervention, prognostic factor or exposure am I considering?
C = Comparison
Is there an alternative to compare with the intervention?
O = Outcome
What do I hope to accomplish, measure, improve or affect?
Sometimes, Time (T) is added to the forumula.
Background questions are general informational questions about a condition, treatment, etc. such as how often a person with a family history of colon cancer should have a colonoscopy.
Two additional important elements of the well-built clinical question to consider are the type of foreground question and the type of study (methodology). This information can be helpful in focusing the question and determining the most appropriate type of evidence.
Foreground questions can be further divided into questions that relate to therapy, diagnosis, prognosis, etiology/harm
Therapy: Questions of treatment in order to achieve some outcome. May include drugs, surgical intervention, change in diet, counseling, etc.
Diagnosis: Questions of identification of a disorder in a patient presenting with specific symptoms.
Prognosis: Questions of progression of a disease or likelihood of a disease occurring.
Etiology/Harm: Questions of negative impact from an intervention or other exposure.
Knowing the type of foreground question can help you select the best study design to answer your question. You always want to look for the study design that will yield the highest level of evidence.
Adapted from Georgetown University Library, http://researchguides.dml.georgetown.edu/ebmclinicalquestions
