ANALYTICAL PERFORMANCE OF AN AUTOMATED ERYTHROCYTE SEDIMENTATION RATE METHOD COMPARED WITH THE WESTERGREN REFERENCE METHOD IN GERIATRIC PATIENTS

Background: The erythrocyte sedimentation rate (ESR) is a widely used nonspecific marker of inflammation. Although theWestergren method remains the reference method for ESR measurement, automated systems offer advantages in terms ofstandardization, reduced manual handling and faster processing. However, automated methods may show analyzer-specificdifferences when compared with Westergren ESR. The present study evaluated the analytical performance of an automatedESR method in geriatric patients using the Westergren method as the reference.Materials and Methods: This hospital- and laboratory-based diagnostic accuracy study was conducted over 12 months inthe Central Laboratory, Department of Pathology, Adesh Institute of Medical Sciences and Research, Bathinda, Punjab. Atotal of 218 geriatric patients aged >60 years were included. Venous blood samples collected in K₂-EDTA tubes wereanalyzed by the ROLLER 20-LC automated ESR analyzer and the conventional Westergren method within 4 hours ofcollection. ESR values were categorized into low (≤20 mm/hour), medium (21–60 mm/hour) and high (≥61 mm/hour)groups. Correlation, sensitivity, specificity and accuracy of the automated method were assessed against the Westergrenmethod.Results: Among the 218 patients, 99 (45.4%) were males and 119 (54.6%) were females. The mean ESR was 61.03 ± 25.65mm/hour by Westergren and 53.25 ± 24.52 mm/hour by the automated method. The automated method showed lower meanESR values than Westergren, particularly in the medium and high ESR groups. The mean difference was −0.68 mm/hour inthe low ESR group (p=0.51), −4.30 mm/hour in the medium group (p<0.001) and −4.93 mm/hour in the high ESR group(p<0.001). A strong positive correlation was observed between automated ESR and Westergren ESR (r=0.9697, p<0.0001).The automated method demonstrated a sensitivity of 0.924, specificity of 1.000 and overall accuracy of 0.929.Conclusion: The automated ESR method demonstrated strong correlation and high classification performance comparedwith the Westergren reference method in geriatric patients. However, the automated method consistently produced lowerESR values, particularly at medium and high ESR concentrations. Therefore, although suitable for routine ESR assessment,analyzer-specific bias should be considered when interpretin