Wilkes University

Evidence-Based Practice and Information Mastery: Evidence Pyramid and Resources

A guide on the method of applying evidence-based practice to combat information overload and help the practitioner locate, evaluate and integrate the best information to improve the quality of care for the patient.

Levels of Evidence

In the medical sciences evidence is often ranked from the strongest to the weakest, with systematic reviews/meta-analyses considered to be at the highest level, or Level 1.  The rankings are based on the characteristics of research designs (methodology, validity, and applicability to patient care) and their ability to protect against bias. 

Some Tools that Rate the Level of Evidence

The resources below are only available to Wilkes staff, faculty and students:

Students 4 Best Evidence

This network for students interested in evidence-based healthcare  brings together relevant, useful resources about all aspects of EBH into a searchable, useable platform.

S4BE is divided up into two main areas, education and blogging. The education component includes both articles generated by S4BE contributors and signposts to outside content.

In addition to the educational aspect, S4BE has student bloggers who write about EBH. Their posts look at recent news in the health world or summarize new research. They also comment on problems and controversies in the health world, trying to find solutions.


EBM Pyramid and Resources

The evidence pyramid is a visual representation of grades of evidence.  For example, a systematic review of randomized controlled trials that show consistent results provides the highest quality evidence (i.e., the “gold standard”) and is at the top of the pyramid. Towards the base we find literature such as case reports or case series which are less likely to reliably predict outcomes. 

When making evidence-based decisions for patient care, it is essential to select the highest level research design available for the specific question of interest. You should recognize that as you move up the pyramid, fewer studies are available; that is, high levels of evidence many not exist for all your clinical questions.  You may need to move down in the pyramid to other types of literature.


Evidence-Based Medicine Websites andTutorials

Primary - Secondary - Tertiary Literature

The advancement of any scholarly field depends on research and the sharing of information that results from that research.  

Primary Sources ("unfiltered information") are publications that report the results of original research may be in the form of conference papers, journal articles, technical reports, theses and dissertations, or journal articles.  The information is present in its original form (that is, it has not been interpreted or condensed or otherwise “repackaged” by other writers). The works present new thinking/discoveries/results and unite them with the existing knowledge base.  

Secondary Sources ("filtered information") are those which are published about the primary literature, that generalize, analyze, interpret, evaluate or otherwise “add value” to the original information, OR which simplify the process of finding and evaluating the primary literature.  Some examples of secondary sources are “review” articles, and indexes such as PubMed or the Cochrane Database of Systematic Reviews.

Tertiary Sources ("filtered information") compile or digest information from primary or secondary sources that has become widely accepted.  They aim to provide a broad overview of a topic, or data, already proven facts, and definitions, often presented in a convenient form. They provide no new information.  These include “reference” types of works such as textbooks, encyclopedias, fact books, guides and handbooks, and computer databases such as Micromedex and Drugs Facts and Comparisons

Resources like Dynamed are often considered both secondary and tertiary sources.