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WHSL Evidence-Based Medicine: The Basic Principles of EBM

This guide supplements WHSL lectures and tutorials on EBM information searching

Clinical Studies and Systematic Reviews

Clinical studies have become normal in health care in the last 50 years, as are randomised trials or controlled trials. There are now more than 20,000 of them published every year.

An easy-to-understand overview of evidence-based medicine and systematic reviews, and their role in evidence-based practice from PubMed Health.

Why is it important for people to be "randomised" in clinical trials? An easy-to-understand overview from PubMed Health.

What does clinical effectiveness mean? 

Understanding the basics of clinical trials: an easy to understand FAQ from ClinicalTrials.gov.

Understanding Comparative Effectiveness Research (CER)

Clinical Effectiveness Research (CER) aims to provide the best information about which health care practices and treatments work for specific patient  populations¹. CER helps to guide decisions that can lead to better health outcomes at many levels, for the general community as well as for the individual, and is concerned with the comparative assessment of interventions in routine practice settings. 

Methods for conducting CER include cohort studies, evidence synthesis such as systematic reviews, observational studies or "pragmatic" randomized controlled trials (RCTs). Pragmatic RCTs differ from conventional RCTs by testing interventions in "real-world" conditions, and allowing adjustments (adaptive designs) based on new information learned as a result of the study, and during its progress.

CER is similar to evidence-based medicine (EBM). Wheras EBM uses RCTs as the primary evidence source, CER studies focus on the effectiveness of interventions in real world practice. EBM can therefore also use CER studies as a source of evidence. 

1. Goodrich, K, Auston, I, Dunn, K, Van Horne, V, & Long, L. 2012. Understanding comparative effectiveness research: Part 1: the controversies and the challenges. MLA News 52(1): 1, 8.