New method for the determination of fecal consistency and its optimal value in the general population.

Background: Although fecal consistency is an important factor, there has been only one study measuring this parameter. We developed a new method to measure fecal consistency and studied the relationship between fecal consistency and other fecal factors, including water content and weight.

Methods: The new method is a modification of the method of Exton-Smith and used an even balance. Subjects in the initial trial were 26 healthy women. Subsequently, fecal consistency was measured in a representative sample of the general Japanese population, in order to evaluate the optimal value to maintain large bowel function.

Results: Correlations between fecal consistency and fecal water content and weight were statistically consistent, although not highly correlated with each other. The optimal mean value was around 300 cm2: 'normal' in 'subjective defecatory state', 295.5 cm2 and 305.2 cm2; 'once/day' in 'defecation frequency', 296.1 cm2 and 310.2 cm2; 'soft and plump' in 'fecal characteristics', 293.6 cm2 and 298.3 cm2, in males and females, respectively. The coefficient of variation of this method ranged from 5.2% to 6.3%.

Conclusions: This method is thought to be applicable to large-scale epidemiological surveys. The optimal value of fecal consistency in the general population was evaluated at approximately 300 g/cm2.