Ask a clear, answerable
The first critical step is to clarify one or two key issues
that come up in the course of caring for your patient and to develop a focused
Without this crucial step, the rest of the steps are
A well-built clinical
question has four components. The mnemonic PICO is useful for
In addition to the PICO
model, there are a number of variations, one of which is PICOTT. This model
reflects that the type of question you are asking will yield various study
- Patient or Population -- Be specific about the group you are
interested in. Consider age, sex, risk profile, or other traits that may be
Intervention -- Again, be specific
about the intervention (or exposure) you are looking for (e.g., treatment with
inhaled corticosteroids, passive smoking, surgical procedure)
- Comparison Intervention -- What alternatives do you
want to compare the intervention to (e.g., standard therapy for asthma, chest
x-ray, watchful waiting)
- Outcome -- Try to be precise, yet brief,
in defining the outcome (e.g. growth delay, diagnostic usefulness)
- T -- What type of question are you asking?
Therapy/Treatment, Diagnosis, Prognosis, Harm/Etiology, Prevention, Quality
- T -- What type of study do you want to find? What would be
the best study design/methodology?
|Type of Question/Domain
|| Type of Study/Methodology
treatments or interventions that do more good than harm and that are worth the
effort and cost.
|Double-Blind Randomized Controlled Trial
interpretation of diagnostic tests, in order to confirm or exclude a diagnosis,
based on considering their precision, accuracy, acceptability, expense, safety,
Systematic Review/Meta Analysis
Estimation of a
patient's likely clinical course over time and anticipation of likely
complications of disease.
Case Controlled Study
causes or risk factors for disease.
In elderly patients, are ACE inhibitors
more effective than beta blockers in controlling high blood pressure and
minimizing adverse effects?
Population is elderly patients, the Intervention is ACE
inhibitors, the Comparison Intervention is beta blockers, and the
Outcome is controlling high blood pressure and minimizing adverse
EXAMPLE QUESTION 2
In children with asthma, are inhaled steroids more likely to
result in growth delay than standard therapy with
The Population is
children with asthma, the Intervention is inhaled steroids, the
Comparison Intervention is beta-agonists and the
Outcome is growth delay.