Asking a Good Question (PICO)

Patients have increasing access to medical and healthcare information on the Internet and are becoming more informed healthcare consumers. Therefore, the clinician's need to access new information and remain current with scientific findings is becoming more critical. The evidence-based approach guides clinicians to form well-built questions that result in patient-centered answers, improving the quality of care.

Asking the right question is a difficult skill to learn, yet it is fundamental to the evidence-based decision-making process. This process almost always begins with a patient question or problem. A "well-built" question should include four parts, referred to as PICO that identify the patient problem or population (P), intervention (I), comparison (C) and outcome(s) (O). 1

The formality of using PICO to frame the question serves three key purposes.

1. It forces the questioner to focus on what the patient/client believes to be the most important single issue and outcome.

2. It facilitates the computerized search, by selecting language or key terms that will be used in the search.1

3. It directs you to clearly identify the problem, results and outcomes related to the specific care provided to that patient. This allows you to determine the type of evidence and information required to solve the problem and to measure the effectiveness of the intervention.

Thus, EBDM supports continuous quality improvements through measuring outcomes of care and self-reflection.

Elements of a Good PICO Question

How to Phrase a Well-Built Question

PICO Resources  
EB Clinical Practice Tutorial, "Designing an Answerable Question"
Center for Evidence-Based Medicine, "Focusing Clinical Questions"
Introduction to EBM, Duke University/UNC, "The Well-Built Question"


  1. Sackett DL, Richardson WS, Rosenberg W, Haynes RB (1997). Evidence-based medicine: How to practice and teach EBM. New York: Churchill Livingston.