The first step in developing a well-built question is to identify the patient problem or population [P] by describing either the patient’s chief complaint or by generalizing the patient’s condition to a larger population. The problem is further shaped or refined by the most important characteristics that might influence the results such as:
In Nathan Baker’s case, we know the chief complaint or the Problem is erosive tooth wear and that his home care, diet, and possibly swimming are contributing factors.
Identifying the Intervention [I] is the second step in the PICO process. It is important to identify what new treatment option is being considered or what the patient is asking about, which keeps the process patient-centered. This may include the use of a specific diagnostic test, treatment, adjunctive therapy, medication, or the recommendation to the patient to use a product or procedure. The Intervention is the new consideration for that patient.4 In Nathan’s case, the intervention being considered is the Sensodyne Pronamel® (a sodium fluoride toothpaste with potassium nitrate).
The third phase of the well-built question is the Comparison [C], which is the main alternative (intervention) you are considering.2 It should be specific and limited to one alternative choice, as is the Intervention. The C is typically the accepted procedure you perform, or the gold standard. Having specified just one “I” and one “C” facilitates an effective computerized search. The Comparison is the only optional component in the PICO question since there may not be an alternative, however when there is one, it should be used. In our case, we have selected the stannous fluoride toothpaste, Crest Pro-Health, as the main alternative.
The final aspect of the PICO question is the outcome [O]. This specifies the result(s) of what you plan to accomplish, improve, or affect. It should be measurable and directly solve the problem. Examples of outcomes are more, or as effective in relieving or eliminating specific symptoms, improving or maintaining function, and enhancing esthetics. In Nathan’s case, you are seeking evidence that demonstrates the effectiveness of Sensodyne Pronamel® toothpaste under a given set of conditions, i.e., effective in preventing tooth erosion. Outcomes yield better search results when defining them in specific terms and they should solve the specific problem. "More effective or just as effective" are not acceptable outcomes unless they describe how the intervention is more effective or just as effective as the Comparison. For our example, more effective in preventing tooth erosion is the desired outcome.