Gastric emptying rate

Method

Emptying of a standardised test meal or drink from the stomach, by 13C-acetate or 13C-octanoate breath test, gamma scintigraphy, or paracetamol (acetaminophen) absorption kinetics, expressed as the half-emptying time in minutes. Method and test-meal composition recorded on the edge; half-emptying time, percentage retained at a fixed time, and the emptying coefficient are three different expressions of the same physiology and are not interchangeable.

The method is part of the endpoint identity. Studies measuring the same quantity by a different method are held as separate endpoints.

Notes

CRITICAL SIGN INVERSION, twice over. First, against the word 'rate' as used everywhere else in this vocabulary: responder rate, graft survival rate, and clinical effective rate all improve by counting MORE events, whereas expressed as a half-emptying time — as this node is — benefit for postprandial glycaemia and satiety is SLOWER emptying and therefore a LONGER time. A source reporting percentage emptied at 60 minutes reports the same physiology with the polarity flipped and must be sign-corrected before it becomes an edge here. Second, the therapeutic direction itself inverts with population: in gastroparesis and in critical-illness feed intolerance FASTER emptying is the benefit, so the direction must be asserted on each edge and not inherited from this node.