Pragmatic evidence and the nature of randomized trials

Here we describe the key elements of the pragmatic approach and the close relationship with the original nature of randomized trials. Our aim is to refocus teaching, research and interpretation of evidence, not as a novel approach but as a return towards the essence of pragmatic evidence and the nature of randomized trials. We first go back to the origin of pragmatism in philosophy and its introduction in medicine and revisit the nature of randomized trials in their pure form. We highlight the critical distinction between assessing treatment decisions and understanding the mechanisms of these decisions. We show why the current view on randomized trials in medicine has lost a pragmatic focus, with the explanatory design features blinding and adherence control often seen as defining characteristics or quality criteria of randomized trials. We then highlight common misunderstandings of pragmatic trials and conclude with an overview of their key features to provide pragmatic evidence.