A Simple Volumetric Device for Preparing Stool Samples in the Cellophane Thick-Smear Technique *

Abstract

We have designed a volumetric device to estimate the weight of stool in the cellophane thick-smear technique; this is a 1-ml plastic syringe sectioned 3 mm from its tip, with a calibrator to ensure a constant displacement of the plunger and hence a constant volume of stool. Statistical analysis showed no significant variation among the weights of stool samples measured in syringes of the same size. There was no significant difference in the weight of 20 random samples when the same syringe and the same calibrator were used. The device is recommended for use in public-health programs on helminthiasis, due to its ease of manufacture, low cost, and reproducibility.