Assessing intra- and inter-analyser imprecision in automated hematological laboratories

Background: Reliable haematology results are crucial for patient diagnosis and monitoring. Maintaining low variability is particularly important for key parameters such as haemoglobin, white blood cells, and platelets, especially in automated laboratory workflows where multiple haematological analysers are connected in the same line. Methods: Two residual whole blood samples, one normal and one pathological, were analysed in ten consecutive replicates on a Sysmex XN-10 analyser (XN-1) and then on a second connected analyser (XN-2). Intra-analyser and inter-analyser imprecision were calculated as coefficients of variation (CV%). Results: Intra-analyser CVs for the normal sample ranged from 0.3% for haemoglobin to 1.5% white blood cells, while inter-analyser CVs remained below 2%. For the pathological sample, intra-analyser CVs ranged from 0.3% to 1.0%, and inter-analyser CVs reached 2.1% for hematocrit and platelets. Red blood cell count, mean corpuscular volume, and neutrophils showed CVs <1.9%. Higher variability was observed for low-abundance populations such as eosinophils and basophils (up to 20%). Conclusions: Sysmex XN-10 analysers exhibit strong intraand inter-analyser precision for most routine haematology tests, supporting their routine use in automated haematological lines.