This latest contribution to the pool of resources at Sportscience is an excellent learning, teaching, and research resource valuable for researchers and research consumers at all levels. In the form of a PowerPoint presentation, it may be used for upper level teaching (in whole or in parts) and also serves as a reference source for experienced researchers. The presentation builds on and complements the Magnitude Matters slideshow and the Progressive Statistics article published in January 2009 in MSSE.

For me, the crux of the presentation is on Slide 6, emphasizing the fact that the right question is not whether there is an effect but how big is the effect. As Will highlights, answering this question requires an a priori definition of the smallest worthwhile effect. This is by no means a trivial task, but it is one that must not be shirked in hiding behind a null-hypothesis testing framework. (As Will once remarked famously from the podium in an ACSM symposium, "if you don't know what matters for your patients or clients, quit the field!") An illustration of the importance of this problem is the recent call by the UK Medical Research Council/ National Institute for Health Research Methodology Research Programme for proposals concerned with "how to specify the targeted difference for a randomised controlled trial." Dr Jonathan Cook (University of Aberdeen) is now leading this project, which will result in draft guidance for researchers and funding bodies, including separate sections for different types of trials and on different ways in which the outcomes of a treatment might be measured