ABSTRACT
Blood samples from 12 normal cases and 30 thalassemic patients were analyzed by four blood cell analysers (the H*1, Baker 9,000RX, Coulter JT, and Argos). These four machines had different technology: light scattering using laser beam (H*1) and electronic aperture impedance (Baker 9,000RX, Coulter JT, and Argos). Analysis of normal blood samples showed comparable red cell parameters between these four machines except the value of RDW. When the thalassemic blood samples were determined using these four types of blood cell counters, many red cell parameters showed significant difference. This indicates that thalassemic red cells which are known as the abnormal cells in terms of their volume, shape, intracellular hemoglobin content, and osmotic fragility, responded differently to the reagents and technology of blood cell analysis. Calibration of the instrument using qualitatively abnormal blood sample, is recommended.