Reproducibility of the proctometrogram.

The reproducibility of a method of measuring rectal distensibility by continuous controlled fluid inflation with a balloon has been evaluated in 15 patients. The volume at sensation threshold, constant sensation and maximal tolerance, the pressures at these volumes and rectal compliance were measured. The mean coefficients of variation of the seven variables measured ranged from 4.7%-7.9%. The expected correlation between rectal compliance and maximal tolerable volume was confirmed (r = 0.85, p less than 0.001). The high reproducibility makes this investigation reliable for use in clinical practice and research.