http://www.hsl.unc.edu/services/tutorials/ebm/Question.htm

The EBM Process | Anatomy of a question

The EBM Process
The Patient
1. Start with the patient: a clinical problem/ question arises out of the care of the patient.
The Question
2. Construct a well-built question derived from the case.

EBM always begins and ends with the patient. To begin this process, consider the following clinical scenario:

Pauline is a new patient who recently moved to the area to be closer to her son and his family. She is 67 years old and has a history of congestive heart failure brought on by several myocardial infarctions.

She has been hospitalized twice within the last 6 months for worsening of heart failure. At the present time she remains in normal sinus rhythm. She is extremely diligent about taking her medications (enalapril, aspirin and simvastatin) and wants desperately to stay out of the hospital. She lives alone with several cats.

You think she should also be taking digoxin but you are not certain if this will help keep her out of the hospital. You decide to research this question before her next visit.

Pauline

The next step in this process is to take the identified problem and construct a question that is relevant to the case and is phrased in such a way as to facilitate finding an answer. This is called "constructing a well built clinical question."

Anatomy of a good clinical question
1. Patient or problem
How would you describe a group of patients similar to yours? What are the most important characteristics of the patient? This may include the primary problem, disease, or co-existing conditions. Sometimes the sex, age or race of a patient might be relevant to the diagnosis or treatment of a disease.
2. Intervention, prognostic factor, or exposure
Which main intervention, prognostic factor, or exposure are you considering? What do you want to do for the patient? Prescribe a drug? Order a test? Order surgery? What factor may influence the prognosis of the patient? Age? Co-existing problems? What was the patient exposed to? Asbestos? Cigarette smoke?
3. Comparison
What is the main alternative to compare with the intervention? Are you trying to decide between two drugs, a drug and no medication or placebo, or two diagnostic tests? Your clinical question does not always need a specific comparison.
4. Outcomes
What can you hope to accomplish, measure, improve or affect? What are you trying to do for the patient? Relieve or eliminate the symptoms? Reduce the number of adverse events? Improve function or test scores?

The structure of the question might look like this:

Patient / Problem
congestive heart failure, elderly

Intervention
digoxin

Comparison, if any
none, placebo

Outcome
primary: reduce need for hospitalization; secondary: reduce mortality

For our patient, the clinical question might be:
In elderly patients with congestive heart failure, is digoxin effective in reducing the need for rehospitalization?