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Health & Society Resources @ UTSC

Search this guide to get started with research in public health.

Research Question Frameworks

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?

  • Develop a focused, answerable research question
  • Identify the main concepts within the research question
  • Generate key terms for each main concept to use in a literature search

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.).

PICO Framework

When can you use the PICO framework? 

  • Clinical research questions (in particular, questions about the effectiveness of interventions)
  • Quantitative research questions
  • Systematic reviews

Elements of the PICO framework

The PICO acronym stands for the following components: (1) patient, population, or problem, (2) intervention, (3) comparison or control (optional), and (4) outcome.

Diagram breaking down the elements of the PICO framework.

PICO Examples by Question Domain

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

Disease or condition

Patient's demographics or characteristics

Procedural intervention


Lifestyle change

Standard care

Comparison intervention


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


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)

Disease or condition

Patient's risk factors

Preventive measure


Lifestyle change

Alternative preventive measure Outcome(s) of interest (e.g. disease incidence, mortality rate)

Extensions of the PICO framework

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):

  • T: time frame
  • T: type of study
  • S: setting

PCC Framework

When can you use the PCC framework? 

  • Quantitative research questions
  • Qualitative research questions
  • Scoping reviews (e.g. recommended by JBI)

Elements of the PICO framework

The PICO acronym stands for the following components: (1) population, (2) concept, and (3) context.

Diagram breaking down the PCC framework

PICo and PEO Frameworks

When can you use the PICo or PEO frameworks? 

  • Qualitative research questions (particularly explorations of experiences)

Note: Don't confuse the PICO and PICo frameworks! They are used for different types of research questions and contain different elements.

Elements of the PICo framework

The PICo acronym stands for the following components: (1) population, (2) interest, and (3) context.

Diagram breaking down the PICo framework.

Elements of the PEO Framework

The PEO acronym stands for the following components: (1) population, (2) exposure, and (3) outcomes.

Diagram breaking down the PEO framework.