It is now more than 50 years since the concepts of explanatory and pragmatic attitudes towards trials were first discussed by Schwartz and Lellouch in their influential 1967 paper. Since then there has been increasing focus on design aspects that may be consistent with more pragmatic attitudes within clinical trials, and a number of tools developed to assist investigators prospectively think about their trial design. Researchers have subsequently expressed interest in using these tools retrospectively to characterise trials as pragmatic or explanatory. We suggest that recent attempts to retrospectively dichotomise trials solely on the basis of quantitative scoring of trial design features are flawed. Instead, we argue that there is a need to consider both the intent and design when assessing the degree of pragmatism within a trial. The practical implication of our suggestion for trial reporting is that investigators should explicitly state the intent of the trial through a clear articulation of the decision that they hope will be informed by the trial results. This should be coupled with a completed PRECIS-2 assessment (or similar) with an explanation of study design choices, in order to appropriately assess whether the study design is consistent with the study intent. We believe this will assist reviewers and knowledge users in making assessments of trials.
- Randomized controlled trial
- quantitative assessment
Nicholls, S. G., Zwarenstein, M., Hey, S. P., Giraudeau, B., Campbell, M. K., & Taljaard, M. (2020). The importance of decision intent within descriptions of pragmatic trials. Journal of Clinical Epidemiology. https://doi.org/10.1016/j.jclinepi.2020.04.030