Nursing 465: PICO

PICO

The first stage of any evidence-based practice process is formulating an answerable question. This forms the foundation for quality searching. A well-formulated question will facilitate the search for evidence and will assist you in determining whether the evidence is relevant to your question.

An answerable question has a format that follows the PICO concept. The acronym translates to:

• P – Populations/People/Patient/Problem
  • Describe the most important characteristics of the patient. This may include their primary problem, disease, or co-existing conditions. Sometimes the sex, age, or ethnicity of a patient might be relevant to the diagnosis or treatment of a disease.
• I – Intervention(s)
  • Which main intervention, prognostic factor, or exposure do you wish to study? What do you want to do for the patient? Educate him about a drug, a test or a surgical procedure? Provide advice on nutrition or exercise?  What factor(s) may influence the prognosis of the patient? Age? Co-existing problems? Exposure to asbestos, cigarette smoke?
• C – Comparison
  • What is the main alternative to compare with the intervention?  Compare two drugs, a drug and no medication or placebo, two diagnostic tests?  Some clinical questions do not have a specific comparison.
• O – Outcome
  • What can you hope to accomplish, measure, improve or affect? What are you trying to do for the patient? Relieve or eliminate the symptoms? Reduce the number of adverse events? Improve function or test scores?

PICO Example:

In patients with chest tubes, does petroleum impregnated gauze reduce catheter dwell times as compared to dry gauze dressing?

P = patients with chest tubes
I = petroleum impregnated gauze
C = dry gauze dressing
O = catheter dwell times

Use AND to combine different concepts that are included in your PICO question.

• chest tube AND petroleum impregnated gauze
• dry gauze AND dwell time

Use OR to combine synonyms.

• chest tube OR chest drain
• gauze OR dressing

Truncation
Use an asterisk * to search for different word endings: 

• drain* = drain, drains, drained, draining, drainage

Use your PICO terms to create a search strategy to find relevant EBM and health databases. Terminology in the health sciences is filled with synonyms, so you may need multiple terms for a each concept.  

CINAHL, PubMed and other databases provide a thesaurus or list of standardized subject headings (called MeSH headings in PubMed) that point to appropriate terms for your search.

(chest tube OR chest drain OR chest catheter)
AND
(gauze or dressing)
AND
(petroleum OR petrolatum)
AND
(dwell time OR time factors)