PICO is a mnemonic for the four elements of a good clinical research question- Patient/Problem, Intervention, Comparison, Outcome. Defining these four elements for your research can generate strong searchable terms for use in literature review.
Research often starts with a general question, such as "how effective is CPR?". The application of PICO to this question allows us- or forces us- to come up with better, more exact, more "searchable" terms. For Patient/Problem, we may focus on an age group, a population, a health cohort, or any other group of potential patients- in this case, we will use healthy adults. Intervention allows us to define how the patient will be treated- CPR is our topic, but for our specific intervention we can focus on hands-only CPR. Since we are looking at hands-only, our Comparison can be traditional hands and breathing CPR. And finally, for Outcome, we need to define "effective"- one measure of this for CPR is mortality. Put together, this forms the PICO question: "In healthy adults, how effective is hands-only CPR versus hands plus breathing CPR at preventing mortality?"
Sometimes, you may see an additional element of a PICO question: time. This fifth element allows for a defined time period for a given treatment or project. Due to this, you may sometimes see PICO written as PICO(T).
For an intervention/therapy:
In _______(P), what is the effect of _______(I) on ______(O) compared with _______(C) within ________ (T)?
For etiology:
Are ____ (P) who have _______ (I) at ___ (increased/decreased) risk for/of_______ (O) compared with ______ (P) with/without ______ (C) over _____ (T)?
Diagnosis or diagnostic test:
Are (is) _________ (I) more accurate in diagnosing ________ (P) compared with ______ (C) for _______ (O)?
Prevention:
For ________ (P) does the use of ______ (I) reduce the future risk of ________ (O) compared with _________ (C)?
Prognosis/Predictions
Does __________ (I) influence ________ (O) in patients who have _______ (P) over ______ (T)?
Meaning
How do ________ (P) diagnosed with _______ (I) perceive ______ (O) during _____ (T)?
Based on Melnyk B., & Fineout-Overholt E. (2010). Evidence-based practice in nursing & healthcare. New York: Lippincott Williams & Wilkins.