Why we will remain pragmatists: four problems with the impractical mechanistic framework and a better solution.

摘要

Pragmatic trials aim to inform a health care decision, whereas explanatory trials focus on understanding [1]. As a consequence, pragmatic trials are undertaken under conditions very similar to the usual care setting, whereas explanatory trials are undertaken under ideal conditions to maximize success. There are two reasons why this distinction between pragmatic and explanatory trials is important. Firstly, it clarifies for investigators how different purposes lead to different decisions in designing a trial and can, therefore, help them to make appropriate decisions. Secondly, it provides funders, ethics committees, trial registers, and journal editors with a framework for considering the extent to which a trial's design is consistent with its purpose. This has implications for approving and registering protocols and for reporting trials. For policymakers (using trials to inform clinical or public health policies), clinicians and patients it is helpful to understand the distinction between pragmatic and explanatory trials, but the distinction is not particularly important, as we will explain.