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Library resource guide for students in the Undergraduate Medicine program.

Evidence-Based Resources



Metasearch Engines

The 6S Hierarchy of Evidence

The 6-S model focuses on appraised literature. Resources at the bottom of the hierachy have not been appraised. Resources from higher on the hierarchy are critically appraised and the evidence is synthesized and often presented in the policy content of a particular country. This model works very well when researching for answers to therapy questions.


[DiCenso, Bayley and Haynes (2009). ACP Journal Club. Editorial: Accessing pre-appraised evidence: Fine-tuning the 5S model into a 6S model. Annals of Internal Medicine, 151(6):JC3-2, JC3-3.]


Clinical Practice Guidelines (CPS)

CPGs are often included in Evidence Summary tools and are captured by metasearches like TRIP

Drug Information



Procedure Videos

Dermatology Decision Support

Patient Handouts


Readability Scores

Are your patients going to be able to understand the handout? You can assess what level of education would be needed by using online readability tests.

PICO : A good search strategy usually contains "P", "I" and "C"

 Patient, Population, or Problem

 How would I describe a group of patients similar to mine?

 Intervention, Prognostic Factor, or Exposure

 Which main intervention, prognostic factor, or exposure am I considering? 


 Comparison or Intervention (if appropriate)

 What is the main alternative to compare with the intervention?

 Outcome you would like to measure or achieve 

 What can I hope to accomplish, measure, improve or affect?

If you cannot find your topic in an Evidence Summary (BMJ Best Practice, Dynamed, UpToDate etc) you will need to search other resources, like Cochrane and PubMed Clinical Queries. PICO can help you translate your clinical question into searchable concepts.



What is the optimal corticosteroid regime for an 8 year old female with steroid-responsive nephrotic syndrome ?

P: child, steroid-responsive nephrotic syndrome

I: corticosteroid

C: randomized controlled trials (RCTs) *


This is how it looks in PubMed Clinical Queries:


* Narrow your results to RCTs by changing the Scope from "Broad" to "Narrow"