Abstract
Randomized trials may be broadly categorized as explanatory or pragmatic. Explanatory trials address the question, ``Can this intervention work under ideal conditions?” Pragmatic trials ask, ``Does this intervention work under usual conditions?'' Usual conditions, of course, are context-dependent. In the United Kingdom, the CALORIES trial by Harvey et al.,
1
reported in the
Journal,
addresses the clinical effectiveness of early enteral nutrition, as compared with early parenteral nutrition, in critically ill patients without contraindications to either route of delivery. This trial, commissioned and sponsored by the Health Technology Assessment Program of the National Institute for Health Research, was pragmatic in design . . .