Calibration methods for automated hematology instruments

Recent CAP survey data have documented marked improvement in the reproducibility of hematologic tests. The favorable outcome is attributable largely to the widespread use of automated whole-blood analyzers. Calibration variability, however, detracts from this enhanced precision, and there are clear indications that improvement is necessary. Primary calibration methods for hemoglobin, hematocrit and cell counting procedures are presented. The methods of applying these primary calibration methods to automated whole-blood analyzers are delineated. The use of both preserved reference blood and statistical control technics for the identification of calibration loss is described.