There are many frameworks used in the health sciences to develop and structure research questions in academic and clinical settings. The frameworks are made up of acronyms representing the key components for different types of research questions.
What are the benefits of using a framework?
The following page describes different frameworks you can use to structure or break down your research question. Choose the most appropriate one for the type of research you're performing (clinical, quantitative, qualitative, etc.).
The PICO acronym stands for the following components: (1) patient, population, or problem, (2) intervention, (3) comparison or control (optional), and (4) outcome.
The table below outlines how the PICO components can vary according to the domain (type) of your question. Please note that the table provides examples and is not meant to be exhaustive. Talk to your instructor or librarian if you need help using the PICO framework for your assignment or project.
| Question Type (Domain) | P | I | C | O |
| Therapy |
Disease or condition Patient's demographics or characteristics |
Procedural intervention Medication Lifestyle change |
Standard care Comparison intervention Placebo No treatment |
Outcome(s) of interest (e.g. management of disease or condition) |
| Etiology (Causation) |
Disease or condition Patient's risk factors |
Exposure to condition or risk factors of interest |
Absence of condition or risk factors |
Outcome(s) of interest (e.g. development of disease or condition) |
| Diagnosis | Disease or condition |
Diagnostic test or tool Procedure |
Reference standard / gold standard tool or procedure Alternative tool or procedure |
Outcome(s) of interest (e.g. measures of test utility such as specificity or sensitivity) |
| Prognosis (Forecast) | Disease or condition | Prognostic factor | None | Outcome(s) of interest (e.g. mortality rate, recurrence) |
| Prevention |
Disease or condition Patient's risk factors |
Preventive measure Medication Lifestyle change |
Alternative preventive measure | Outcome(s) of interest (e.g. disease incidence, mortality rate) |
Certain research questions may have additional elements. These can be incorporated into the PICO framework using the following letters (as PICOT, PICOS, PICOTT, PICOTS, or PICOTTS):
The PICO acronym stands for the following components: (1) population, (2) concept, and (3) context.
Note: Don't confuse the PICO and PICo frameworks! They are used for different types of research questions and contain different elements.
The PICo acronym stands for the following components: (1) population, (2) interest, and (3) context.
The PEO acronym stands for the following components: (1) population, (2) exposure, and (3) outcomes.
