Wednesday, August 30, 2023

Formulating Research Questions :The PICOTS and PICO Frameworks

 1. Foundation

 Key Terms and Concepts

- PICO: An acronym that delineates the four elements essential for formulating a well-structured clinical research question: Population (P), Intervention (I), Comparison (C), and Outcome (O) (Wikipedia, 2021).


- PICOTS: An extension of PICO, incorporating Time (T) and Study Type (S) as additional elements, further refining the research question (University of Edinburgh, 2021).

Both the PICO and PICOTS frameworks serve as invaluable tools in evidence-based medicine for comparing the effects of interventions or exposures on health outcomes. The essential elements are as follows:

- Population: Refers to the specific group, defined by variables such as age, gender, or diagnosis, that is the subject of the study.

- Intervention: The primary exposure or treatment under investigation, which may range from medications to behavioral interventions.

- Comparison: Represents the control group or condition against which the intervention is assessed.

- Outcome: The specific health effect being studied, whether it be a disease, symptom, or quality of life indicator.

- Time frame: The period during which the study takes place and the data are collected.

- Study Design: Specifies the type of study and its inherent strengths and limitations.

The PICOTS framework encompasses all six elements, while the PICO framework omits 'Time frame' and 'Study Design' (Pubrica, 2021).

 2. History and Evolution

 Origin and Evolutionary Milestones

The PICO framework was initially proposed in the 1990s as part of the evidence-based medicine (EBM) movement, with the objective of enhancing clinical decision-making through the integration of the best available research evidence (Richardson et al., 1995). Dr. David Sackett, a pivotal figure in EBM, significantly contributed to this initiative.

The PICOTS framework represents an evolution of the PICO model, incorporating 'Time' and 'Study Design' to allow a more nuanced and comprehensive research question (Cochrane Collaboration, 2019). Several organizations, such as the Agency for Healthcare Research and Quality (AHRQ) and the Cochrane Collaboration, have endorsed this expanded framework.

 3. Key Concepts and Theories

 Foundational Ideas and Theoretical Constructs

The essential theories that underpin the PICO and PICOTS frameworks include:

- Question Framing: A well-structured research question is crucial for the integrity and relevance of scientific inquiry (Sackett et al., 1996).


- Intervention or Exposure: These act as determinants of health outcomes and are central to the framework's utility in research (Higgins et al., 2019).

 Significant Contributors

- W.S. Richardson et al.: Introduced the PICO framework to aid in the formulation of clinical research questions (Richardson et al., 1995).


- D.L. Sackett et al.: Promoted the concept of evidence-based medicine, thereby laying the groundwork for frameworks like PICO (Sackett et al., 1996).

- J.P.T. Higgins et al.: Incorporated the PICOTS framework into the Cochrane handbook for systematic reviews, further legitimizing its use in evidence-based research (Higgins et al., 2019).

 4. Applications

 Real-world Implementations

The PICO framework is widely utilized in healthcare research for the formulation of clinical questions, literature reviews, and evidence appraisal. For instance, a study might ask, "In adults with hypertension, does a new medication lower blood pressure more effectively than current standard treatment over a 12-month period?"

 5. Critical Analysis

 Controversies and Critiques

The elements of the PICOTS framework can sometimes be viewed as inapplicable or redundant, depending on the research question or type of study. However, the framework predominantly serves intervention questions and might not be as adaptable for questions relating to diagnosis or prognosis.

 6. Future Trends and Research

 Emerging Paradigms

Incorporating patient values into evidence-based practice is becoming increasingly important, leading to potential refinements of the PICO and PICOTS frameworks.

 7. Synthesis

The PICO and PICOTS frameworks serve as foundational tools in evidence-based medicine. While they offer a structured approach to formulating research questions, they are not without limitations. Future research aims to refine these frameworks by incorporating patient values and preferences.

 8. Application

 Practical Utility

Clinicians and researchers can apply the PICO framework to structure their research questions, facilitating a more efficient literature search and decision-making process.

 9. Review

The PICO framework remains a cornerstone in evidence-based medicine, guiding researchers in formulating clinical questions. Although the framework has evolved into PICOTS, incorporating 'Time' and 'Study Type,' ongoing research aims to further refine its application.

 10. Modern Concepts

- Shared Decision-Making: An emerging trend where patients actively participate in their healthcare decisions.


- Patient-Centered Care: An approach that focuses on individual patient needs and values, offering a more holistic view of healthcare.

 11. Myths

- Limited to Randomized Controlled Trials: While the PICO framework is well-suited for intervention-based questions, it is adaptable for other types of studies as well.

- Exclusively for Clinicians: Despite its clinical origins, the PICO framework is also employed by researchers, students, and other healthcare professionals.


- Richardson, W.S., Wilson, M.C., Nishikawa, J., & Hayward, R.S. (1995). The well-built clinical question: a key to evidence-based decisions. ACP Journal Club, 123(3), A12-A12.


- Sackett, D.L., Rosenberg, W.M., Gray, J.A., Haynes, R.B., & Richardson, W.S. (1996). Evidence-based medicine: what it is and what it isn't. BMJ, 312(7023), 71-72.

- Higgins, J.P.T., Thomas, J., Chandler, J., Cumpston, M., Li, T., Page, M.J., & Welch, V.A. (Eds.). (2019). Cochrane Handbook for Systematic Reviews of Interventions. John Wiley & Sons.

- Wikipedia. (2021). PICO process. Retrieved from


- University of Edinburgh. (2021). PICOS/T, PEO, PICo, SPIDER Frameworks. Retrieved from

- Pubrica. (2021). What are the PICO elements in systematic review?. Retrieved from

- Cochrane Collaboration. (2019). Cochrane Handbook for Systematic Reviews of Interventions. Retrieved from

- Agency for Healthcare Research and Quality (AHRQ). (2019). Methods Guide for Effectiveness and Comparative Effectiveness Reviews. Retrieved from