• prokinetic
• motilin
• dyspepsia
• gastric motility
• diabetes
• postprandial

I read with great interest the paper by Talley and colleagues (Gut 2001;49:395–401) and the accompanying editorial by Tack and Peeters (Gut 2001;49:317–8). There are many important issues that are raised in the paper and editorial. I believe the paper provides an opportunity to identify areas where study design might be enhanced in future studies.

Firstly, the fact that gastric emptying was not measured at the end of the study leaves wide open the question of whether the prokinetic approach should be abandoned in the treatment of dyspeptic symptoms in diabetics. Thus it would be inappropriate to conclude from this study that prokinetics are not indicated. This point is also emphasised in the editorial by Tack and Peeters.

Secondly, the authors conclude that baseline gastric emptying does not influence the response to ABT-229. This conclusion is based on weak foundations as the method used to measure gastric emptying appears to provide data that are scarcely believable. Thus the t50% recorded in healthy subjects (130±50 (SD?) minutes) is remarkably outside the normal range reported using the gold standard scintigraphy (mean 110±4 (SEM) minutes, 10th percentile 70 minutes, 90th percentile 150 minutes in our laboratory). The methods section does not unequivocally state what mathematical analysis was used with the stable isotope breath test at the central laboratory used in the study. Improved mathematical analyses of gastric emptying using breath tests in the more recent literature provide a higher level of accuracy relative to scintigraphy.^1–,⁴ It is claimed that the method was validated in 19 diabetics in whom …