P: "Patient," "Population," or "Problem" (medical condition/disorder plus age, gender, ethnicity, or other characteristics)
I: "Intervention" or "Indicator" (treatment, therapy, diagnostic test)
C: "Comparison" or benchmark (an alternative intervention, a placebo, or absence of disease)
O: "Outcome" or anticipated result of intervention (what it will affect)
T: "Time" (the time it takes the intervention to achieve an outcome)
This graphic ranks different types of publications and research activities according to their basis in evidence, with systematic reviews considered the strongest form of evidence-based literature.
Source: SUNY Downstate/Medical Research Library of Brooklyn, http://library.downstate.edu/EBM2/2100.htm
The PICO(T) format can help you develop a clear, answerable research question and decide what type of evidence you are looking for. The templates below can help you form a research question (note that not every question may contain all PICO(T) elements).
Some sample PICO templates:
For an intervention or therapy:
In _______(P), what is the effect of _______(I) on ______(O) compared with _______(C), within ________ (T)?
For a diagnosis or diagnostic test:
Are (is) _________ (I) more accurate in diagnosing ________ (P) compared with ______ (C) for _______ (O)?
For prevention questions:
For ________ (P) does the use of ______ (I) reduce the future risk of ________ (O) compared with _________ (C)?
Based on Melnyk B., & Fineout-Overholt E. (2010). Evidence-based practice in nursing & healthcare. New York: Lippincott Williams & Wilkins.