Method Verification of the Caretium XC-A30 Automated Erythrocyte Sedimentation Rate Analyser for Erythrocyte Sedimentation Rate

BACKGROUND: The erythrocyte sedimentation rate (ESR) analyser is widely used in haematological testing. In addition to the Westergren method, new automatic methods for ESR measurements have been developed. We aimed to study the reliability, precision, accuracy and stability of the Caretium XC-A30 automated ESR analyser. METHODS: Ethylenediamine tetraacetic acid (EDTA)-treated blood samples were analysed via the Caretium XC-A30 automated ESR analyser and the Westergren method to compare accuracy. Precision was assessed using control samples and patient samples were classified into three groups—low, medium and high—according to their rates of sedimentation. Moreover, a stability test was performed. RESULTS: The correlation coefficient of the results of the Caretium XC-A30 and Westergren analyses was 0.97. The correlation coefficient of ESR values obtained from the two methods assessed in the low, medium and high groups were r = 0.80, r = 0.68 and r = 0.74, respectively. The coefficient of variation of within-run (%CVw) and between-run (%CVb), with replicates performed with commercial controls samples, were 7.54% and 8.04% for the normal control and 4.68% and 3.50% for abnormal control, respectively. The %CVw obtained with patient samples in the low, medium and high groups were 10.68%, 13.13% and 4.45%, respectively. The Caretium XC-A30 measurements were stable for up to 24 h when samples were stored at 4 °C. CONCLUSION: The Caretium XC-A30 ESR analyser proved to be a suitable instrument for routine analysis of ESR.