Formulating a strong clinical question is the first step in the research process. PICO is a way of building clinical research questions that allow you to focus your research, and to create a query that better matches most medical databases.
Example: In a (describe patient) can (intervention A) affect (outcome) compared with (intervention B)?
Think about the keywords for each of the PICO parts of the clinical question.
Sample Question: Is prophylactic physical therapy for patients undergoing upper abdominal surgery effective in preventing post-operative pulmonary complications?
The PICO parts with keywords for this question would look like this:
| Parts of Question | Clinical Scenario | Keywords |
| Patient Population | patients undergoing upper abdominal surgery | upper abdominal surgery |
| Intervention | prophylactic physical therapy | prophylactic physical therapy |
| Comparison (if any) | no prophylactic physical therapy | none |
| Outcome | prevent post-operative pulmonary complications | prevent pulmonary complications |
| Type of Study | RCT | Randomized Control Study |
You might also see PICO with an added T. The T often stands for either “time” or “type of study.” Time helps you consider the timeframe of an intervention or outcome, while type of study is a way to define the types or levels of evidence that you will need in order to answer your question.
Different types of information provide different standards or levels of evidence. These levels depend on things like a study's design, objectives, and review process. You may be familiar with a pyramid diagram showing a hierarchy of types of evidence. Often included in pyramids of evidence are the following types of information:
The pyramid hierarchy places some types of evidence above others in terms of validity, objectivity, and transferability. It’s important to remember, however, that the best type of evidence to answer your research question depends on the nature of your question and what purpose you have for searching for evidence in the first place. Conducting a literature review, for example, is a very different situation than searching for an answer to a specific question about a particular case, patient, or situation.
Evaluation Criteria:
Credibility: looks at truth and quality and asks, "Can you believe the results?"
Some questions you might ask are: Were patients randomized? Were patients analyzed in the groups to which they were (originally) randomized? Were patients in the treatment and control groups similar with respect to known prognostic factors?
Transferability: looks at external validity of the data and asks, "Can the results be transferred to other situations?"
Some questions you might ask are: Were patients in the treatment and control groups similar with respect to known prognostic factors? Was there a blind comparison with an independent gold standard? Were objective and unbiased outcome criteria used? Are the results of this study valid?
Dependability: looks at consistency of results and asks, "Would the results be similar if the study was repeated with the same subjects in a similar context?"
Some questions you might ask are: Aside from the experimental intervention, were the groups treated equally? Was follow-up complete? Was the sample of patients representative? Were the patients sufficiently homogeneous with respect to prognostic factors?
Confirmability: looks at neutrality and asks, "Was there an attempt to enhance objectivity by reducing research bias?"
Some questions you might ask are: Were 5 important groups (patients, care givers, collectors of outcome data, adjudicators of outcome, data analysis) aware of group allocations? Was randomization concealed?
Users' Guides to the Medical Literature by Other good resources for both appraisal and applying evidence in clinical practice can be found on these two websites:
Ask yourself: