Errors and Variations in White-Cell Counts

Abstract

White blood cell counts are analyzed for variations among hemacytometers, pipettes, and technicians. Since the components of error due to pipettes and hemacytometers are large, overall error cannot be reduced significantly by counting large numbers of cells as might be done with an electronic cell counter. Differential count errors are also found to contribute substantially to overall error. Accordingly, any special staining technique which distinguishes individual cells in the wet count is recommended.