Subject Guides: Occupational Therapy: Evidence-based practice

PICO: Asking answerable questions

Most databases are terrible at accepting natural language queries.

When you are searching for evidence for or against a specific treatment, therapy, or intervention, guessing at keywords can be difficult.

PICO is an acronym for:

Patient (or population) - what describes the person, condition, or situation?
Intervention - What treatment are you looking at?
Comparison (or control) - Are you comparing the intervention to another treatment? To a placebo? To a lack of treatment? (The first case is generally easy, the last two might use search terms, or might not use any search terms at all. It can be common to leave this blank when searching for evidence comparing an intervention to placebo or untreated patients)
Outcome(s) - Are you looking for improvement in a specific measurable symptom? A reduction in pain? An improvement in strength or mobility or time taken to perform a task? (Sometimes this line might be blank).

PICO is a way of selecting keywords for a database search where the results can help you answer a clinical-style question.

For PICO, mostly this is a yes/no or A/B question: Does intervention A produce a better improvement of symptoms than treatment B? Is treatment C better than placebo? Did this change produce an improvement of symptoms?

PICO is a particularly useful technique for finding quantitative evidence. It will work for qualitative evidence, but keep in mind there are other keyword selection techniques which are sometimes more useful for finding qualitative evidence.

Finding the original evidence

Searching for journal articles in Library databases allows you to build up your own set of evidence when trying to decide whether a specific intervention is useful, or better than another intervention, or worth trying.

Often you will have database access after graduation via your employer, or a direct subscription, or free or open access databases (e.g. PubMed, OTDBASE), or as a benefit of membership in a professional association.

Some databases you might wish to search are:

CINAHL Complete This link opens in a new window
CINAHL Complete is the world’s most comprehensive source of full-text for nursing & allied health journals, providing full text for more than 1,300 journals indexed in CINAHL. This authoritative file contains full text for many of the most used journals in the CINAHL index, with no embargo. CINAHL Complete is the definitive research tool for all areas of nursing & allied health literature.
PubMed This link opens in a new window
Covers biomedical literature as a search tool for accessing literature citations and linking to full-text journals at web sites of participating publishers.
Scopus (Elsevier) This link opens in a new window
A multidisciplinary navigational tool that contains records going back to 1966, offering newly-linked citations across the widest body of scientific abstracts available in one place. Coverage includes scientific, technical, medical and social science literature.
Web of Science This link opens in a new window
Data, books, journals, proceedings & patents, Web of Science provides a single destination to access reliable, integrated, multidisciplinary research. Quality, curated content delivered alongside information on emerging trends, subject specific content and analysis tools make it easy for students, faculty, researchers, analysts, and program managers to pinpoint relevant research to inform their work.

Pre-digested evidence

Some databases contain the results of existing work where a professional has already searched for evidence and come to a conclusion on best practice based on the evidence discovered.

Such databases usually contain systematic reviews, evidence synopses (also known as evidence summaries), best practice guidelines, and/or clinical practice guidelines.

Sometimes you can find such reviews published as regular journal articles, sometimes you need to check an evidence-based database.

Some databases where you can find these existing evidence reviews and conclusions are:

Cochrane Library This link opens in a new window
Material on the effects of interventions in health care. Hosted on the Wiley InterScience platform. The Library comprises the following databases: The Cochrane Database of Systematic Reviews; Database of Abstracts of Reviews of Effectiveness; The Cochrane Controlled Trials Register. The NHS Economic Evaluation database. The Cochrane Database of Methodology Reviews. Health Technology Assessment Database.
JBI (Ovid) This link opens in a new window
Resources for evidence-based research including Best Practice information sheets, systematic reviews and electronic journals and conference papers.
(Formerly known as Joanna Briggs Institute.)
This version, via the Ovid interface, should be faster for most users.
Trip Database This link opens in a new window
Online since 1997, Trip (formerly Turning Research Into Practice) is a search engine for quickly finding high-quality health research evidence to support and inform clinical practice.