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Evidence Based Medicine

This guide is designed to assist health care professionals and students become effective and efficient users of the medical literature.

Upcoming Revision

The Evidence Based Medicine Guide will be undergoing a major update on Tuesday May 31st. 
We ask for your patience as parts of the guide may be unusable at various times throughout the day.

Please take a short survey to help improve this guide and to better serve guide users.


What is the PICO Model?

EBM Pyramid


Defining a clinical question in terms of the specific patient problem aids the searcher in finding clinically relevant evidence in the literature.  The PICO Model is a format to help define your question.


The P.I.C.O. Model for Clinical Questions 


Patient, Population, or Problem

How would I describe a group of patients similar to mine?


Intervention, Prognostic Factor, or Exposure Which main intervention, prognostic factor, or exposure am I considering?


Comparison or Intervention (if appropriate) What is the main alternative to compare with the intervention?


Outcome you would like to measure or achieve What can I hope to accomplish, measure, improve, or affect?
  What Type of question are you asking? Diagnosis, Etiology/Harm, Therapy, Prognosis, Prevention
  Type of Study you want to find What would be the best study design/methodology?


Please feel free to view this lecture on the PICO model

This lecture focuses on developing clinical questions and learning how the PICO format can aid our search for the best clinical evidence. 

Background vs. Foreground Questions

When Should I Use the P.I.C.O. Model?

Background questions concern general knowledge.   These types of questions generally have only 2 parts:

  • A question root (who, what, when, where, how, why) and
  • a disorder, test, treatment, or other aspect of health care.  

Often these questions can best be answered by using a textbook or consulting a clinical database.

Foreground questions are specific knowledge questions

  • that affect clinical decisions and 
  • include a broad range of biologic, psychological, and sociologic issues. 

These are the questions that generally require a search of the primary medical literature and that are best suited to the PICO format.


PICO Tools

Contact Us

This guide has been created by the University of Illinois at Chicago's Library of the Health Sciences at Peoria. 
Please feel free to contact us with any questions at