GASTRIC EMPTYING BREATH TESTS

A breath test and a breath test method for diagnosing abnormal gastric emptying using a 13C labeled breath test meal by identifying the time of maximum excretion of 13CO2 in the breath samples. The test and test method include supplying a subject with the breath test meal, collecting a breath sample of the subject at a plurality of time points after the subject consumes the meal, generating measurements of 13CO2 excretion from the breath samples, identifying a time Tmax at which 13CO2 excretion is maximal, comparing Tmax to a cut-off value. The subject may be diagnosed as having delayed gastric emptying if Tmax is greater than the Tmax cut-off value.