Designing pragmatic trials-what can we learn from lessons learned?

Pragmatic trials aim to inform clinical decision making by measuring the effect of a treatment in clinical practice. The purpose of the PRECIS-2 tool is to support in designing a truly pragmatic trial. We comment on a study by Forbes et al., who assessed the applicability of the PRECIS-2 tool. The tool will prove particularly useful when implemented in the process of trial design. However, it is yet unclear how e.g., possible dependencies between PRECIS domains, or conducting a pragmatic trial within an existing data registry (e.g., electronic health records) affect the applicability of the tool.