Bias: the biggest enemy
Posted on May 21, 2013 by Donatas Zailskas
Name of resource:
QMP – Medical Statistics Online Tutorial: Bias – the biggest enemy 
What does it cover?
The tutorial teaches about one of the biggest enemies of strong evidence in clinical research – bias, as well as measurements and outcomes in the clinical trial. It starts with a flowchart describing all the steps needed to design a clinical trial. Each step is explained in a more detailed manner highlighting the key aspects and providing the reader with a few short quizzes. Along the way the readers are introduced to six possible opportunities for bias: bias of subjects and population source, confounding, bias during the intervention, bias in the measurement of outcomes, compliance and attrition, and external validity assessing. The tutorial also provides the reader with possible “anti-biases” to help minimize their effects on the results.
Who is it aimed at?
This tutorial was created by the University of South Wales in Australia and is meant to teach young medical students and newly graduated doctors.
How long will it take to finish?
Depending on your level of interest and knowledge about evidence-based medicine, it could take you from 1 to 2 hours to complete.
I found this tutorial to be very helpful, since it explains some very basic yet extremely important points about clinical research in a very simple manner. I’d recommend it to everyone looking for simple, clear and interactive lessons with a few exercises. I had a pleasant opportunity to revise some of the material I already know and re-organize my notes as well as learn a lot of new information.
 Rachel Thompson, Mike Bennett, Ed Loughman. QMP Medical Statistics Tutorial: Bias – the biggest enemy [Internet]. University of New South Wales, Faculty of Medicine; 2008 [updated 15 March 2013; cited 21 May 2013]. Available from: http://web.med.unsw.edu.au/QMP/QMPTut5_2012/Tut5_Intro.htm