As we saw on the previous page, the first step in the evidence-based practice process is to formulate a clinical question.
The clinical question should be relevant to the patient or the problem and formulated in such a way as to help with the search for an answer.
The PICO concept is commonly used to formulate the clinical question. Each of the 4 letters identifies a key concept that needs to be in research articles that will answer the question:
|P||Patient/Population/Problem||Start with the patient, or group of patients, or problem.|
|I||Intervention||What is the proposed intervention?|
|C||Comparison||What is the main alternative, to compare with the intervention?|
|O||Outcome||What is the anticipated or hoped-for outcome?|
PICO is commonly used when one intervention is being compared with another, or with no intervention at all.
Another acronym that is sometimes used is PICOTT. The extra letters are for:
T Type of Question You can have questions of different types. They can be categorised as a diagnosis, prognosis, therapy, aetiology/harm, or prevention question.
T Type of Study This asks what study design would best answer the question: randomised controlled trial; cohort study; case controlled study; case series; case series; case report etc. For more information on the types of research you will encounter when searching for evidence based practice information please see the Types of Research page in our Evidence-Based Practice Guide.
Here is a medical example of a clinical problem formulated using PICO:
"I work in an aged care facility where urinary tract infections are a common problem. I've heard that cranberry juice can help prevent UTIs. I wonder if there's any evidence for that and whether it might help our patients?"
|P||Patients in aged care homes|
|C||No intervention (status quo)|
|O||Prevention of UTIs|
The SPIDER tool can be used when dealing with qualitative research questions, that is, when the research is about attitudes and experiences rather than scientifically measurable data. It focuses less on the intervention and more on the design of the study, and deals with "samples" rather than "populations".
|S||Sample||The group of participants in qualitative research|
|PI||Phenomenon of Interest||The how and why of behaviours and experiences|
|D||Design||How the study was devised and conducted|
|E||Evaluation||Measurement of outcome might be subjective and not necessarily empirical|
|R||Research Type||Qualitative, or quantitative, or mixed?|
Professor Paul Glasziou from the University of Oxford's Centre for Evidence-Based Medicine (CEBM) talks about forming a PICO question.
Includes information on the different types of questions. (From the Medical University of North Carolina Libraries)
Information on PICO and SPIDER but also on other ways of structuring a research or clinical question. (From the University of Notre Dame Library, Australia)
This article looks at using PICO and SPIDER as tools to help in literature searching.
Cooke, A., Smith, D., & Booth, A. (2012). Beyond PICO: The SPIDER tool for qualitative evidence synthesis. Qualitative Health Research, 22(10), 1435-1443. doi:10.1177/1049732312452938