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Evidence-Based Clinical Practice

A guide to EBCP and resources.

Where to start?

Once you've asked your Clinical Question in the PICO format, you can start your search in PubMed.  See the search terms box to the right to assist in selecting the appropriate terms from your PICO question.  Further assistance can be found by clicking the PubMed Guide available at the link below.  


Need Help?

Need Help Searching?  Take a class, request one on one training, or check out one of our online guides.

Formulate a Search Strategy

The PICO format for clinical questions, detailed on the Step 1: Ask page of this guide, helps to guide your search for evidence in two ways:

  1. By simplifying the question, it helps to clarify the type of clinical question you are asking (e.g., therapy, etiology). The type of clinical question indicates which study designs are best suited to answer your question.
  2. It allows you to identify the most important elements of your clinical question. These concepts are used to create search terminology.

Search Terms

We can translate the natural language from our PICO components into keywords and subject headings (e.g., MeSH). You don't necessarily need to create search terms for every component.

Take this PICO question for example: In patients on oral antibiotics, do probiotics prevent diarrhea?



Intervention Comparison Outcome
PICO Elements In patients on oral antibiotics do probiotics none prevent diarrhea?
Pubmed Search Terms antibiotics OR "anti-bacterial agents"[Mesh] OR "anti-bacterial agents"[Pharmacological Action] probiotics OR "Probiotics"[Mesh]   diarrhea OR "Diarrhea"[mesh]
Full Search Strategy (antibiotics OR "anti-bacterial agents"[Mesh] OR "anti-bacterial agents"[Pharmacological Action]) AND (probiotics OR "Probiotics"[Mesh]) AND (diarrhea OR "Diarrhea"[mesh])

Study Design

Different types of clinical questions are best answered by different types of research studies. 

You might not always find the highest level of evidence (i.e., RCT, systematic review/meta-analysis) to answer your question. When this happens, work your way down to the next highest level of evidence.

This table suggests study designs best suited to answer different types of clinical question.
Clinical Question Suggested Research Designs

All Clinical Questions

Systematic review, meta-analysis


Randomized controlled trial (RCT), meta-analysis
Also: cohort study, case-control study, case series


Randomized controlled trial (RCT), meta-analysis, cohort study
Also: case-control study, case series


Randomized controlled trial (RCT)
Also: cohort study


Randomized controlled trial (RCT), meta-analysis
Also: prospective study, cohort study, case-control study, case series


Cohort study
Also: case control study, case series

Quality Improvement Randomized controlled trials (RCT)
Also: qualitative study

Economic evaluation