The Registry-Based Randomized Trial - A Pragmatic Study Design

Randomized controlled trials are the gold standard of clinical research for comparing therapies in well-defined groups of participants.¹ Randomization avoids confounding due to unmeasured variables or to treatment selection and enables a causal interpretation of the estimated treatment effect. It has long been recognized, however, that standard explanatory clinical trials are slow, costly, and subject to participant selection. To preserve the strengths of randomized trials while mitigating their weaknesses, pragmatic randomized clinical trials emerged; these trials aim to facilitate decision-making rather than explicate a mechanism of action and enroll a diverse set of participants using existing structures and data sources.².