Evidence-based practice uses the PICO model for formulating a searchable 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 = Outlook
What do I hope to accomplish, measure, improve or affect?
PICO helps you to break a clinical problem into important concepts and formulate a searchable question that can be answered with research.
1. Begin with a clinical problem:
2. Express the problem using PICO:
Athlete with partial ACL tear
stable functioning knee
3. Formulate the problem as a research question:
|Question Type||Patient Problem or Population||Intervention or Exposure||Comparison or Control||Example Outcome Measures|
|Therapy (Treatment)||Patient's disease or condition.||A therapeutic measure, eg., medication, surgical intervention, or life style change.||Standard care, another intervention, or a placebo.||Mortality rate, number of days off work, pain, disability.|
|Prevention||Patient's risk factors and general health condition.||A preventive measure, e.g., A lifestyle change or medication.||Another preventative measure OR maybe not applicable.||Mortality rate, number of days off work, disease incidence.|
|Diagnosis||Specific disease or condition.||A diagnostic test or procedure.||Current "reference standard" or "gold standard" test for that disease or condition.||Measures of the test utility, i.e. sensitivity, specificity, odds ratio.|
|Duration and severity of main prognostic factor or clinical problem.||Usually time or "watchful waiting".||Usually not applicable.||Survival rates, mortality rates, rates of disease progression.|
|Etiology (Causation)||Patient's risk factors, current health disorders, or general health condition.||The intervention or exposure of interest. Includes an indication of the strength/dose of the risk factor and the duration of the exposure.||Usually not applicable.||Survival rates, mortality rates, rates of disease progression.|
Once you have clearly identified the main elements of your question using the PICO framework, it is easy to write your question statement. The following table provides some examples.
|Question Type||Patient Problem or Population||Intervention or Exposure||Comparison or Control||Outcome Measure|
|Therapy||In patients with osteoarthritis of the knee||is hydrotherapy more effective than||traditional physiotherapy||in relieving pain?|
|Prevention||For obese children||does the use of community recreation activities||compared to educational programs on lifestyle changes||
reduce the risk of diabetes mellitus?
|Diagnosis||For deep vein thrombosis||is D-dimer testing or||ultrasound||more accurate for diagnosis?|
|Prognosis||In healthy older women that suffer hip fractures||within the year after injury||what is the relative risk of death?|
|Etiology||Do adults||who binge drink||compared to those who do not binge drink||have higher mortality rates?|
1. Schardt, C., Adams, M. B., Owens, T., Keitz, S., & Fontelo, P. (2007). Utilization of the PICO framework to improve searching PubMed for clinical questions. BMC Medical Informatics and Decision Making, 7, 16. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1904193/
2. Fineout-Overholt, E., & Johnston, L. (2005). Teaching EBP: asking searchable, answerable clinical questions. Worldviews On Evidence-Based Nursing, 2, 157-160.