Cutaneous electrogastrography (EGGc), the recording of gastric electrical activity from the cutaneous abdominal surface, still presents a series of difficulties connected with the interpretation of signals. In this study, the authors evaluated the reproducibility of electrogastrographic data over a period of time by making recordings on three consecutive days in a group of healthy subjects. The recordings (lasting 1 hour) were made in the morning on fasting subjects. Three sets of bipolar cutaneous electrodes were placed on the abdomen around the pyloric radiological projection and the couple 3-6 corresponded to the antral axis. The spectral analysis of data was computed by fast Fourier transform. Their data confirmed that the 3-6 couple, corresponding to the antral axis, provides the strongest EGG signal. Each subject's mean gastric frequency and power were evaluated on the three consecutive recording days. The mean frequency was 2.83 +/- 0.22, 2.89 +/- 0.23, and 2.86 +/- 0.16 cpm on day I, day II and day III respectively. The mean power was 54.80 +/- 21.34, 46.86 +/- 21.52 and 49.25 +/- 19.55 microV 2 on day I, day II and day III respectively. The analysis of variance showed that the mean gastric frequency and power were not significantly different on the three days (p > 0.05). This shows that the frequency of the EGGc signal remains stable in the course of time and hence that EGGc is a reliable method of studying disorders in gastric electrical rhythm.(ABSTRACT TRUNCATED AT 250 WORDS)