Objective: To assess the accuracy of the Hemacytometer (Hausser Scientific, Horsham, PA), Makler (Sefi-Medical Instrument, Haifa, Israel), Cell-VU (Millennium Sciences Inc., New York, NY), and Micro-Cell chambers (Conception Technologies, San Diego, CA) counting chambers.
Design: A solution containing a known concentration of latex beads was used as the standard to perform counts on the four different counting chambers.
Main outcome measures: Bead counts for the four different chambers were compared with the bead counts of the standard solution. Variability within chambers also was determined.
Results: Mean bead concentrations for both the Cell-VU and Micro-Cell chambers were consistently similar to the bead concentration of the standard solution. Both the hemacytometer and the Makler chambers overestimated the actual bead concentration of the standard solution by as much as 50% and revealed significant interchamber variability.
Conclusions: Our data revealed marked differences in the accuracy and reliability of the different counting chambers tested and emphasized the need for standardization and quality control of laboratory procedures.