The erythrocyte sedimentation rate (ESR) has been commonly ordered in hematology laboratories and used to screen for monitoring responses to therapy and identifying inflammatory conditions. To overcome the limitations of traditional ESR measurements, various methods have been developed and compared to the established reference method. This study evaluates the analytical performance of ESR fast detector and Improve® ESR analyzer compared to the reference method. Method validation and comparison were performed in 189 volunteer blood samples according to the International Council for Standardization in Hematology recommendations. The analytical efficacy of ESR fast detector and Improve® ESR analyzer was also assessed and compared with the reference method and C-reactive protein (CRP) levels. The results demonstrated that the precision of ESR fast detector and Improve® ESR analyzer was considered as the acceptance criterion for the ESR measurement. The method comparison analysis between the two modified Westergren methods and reference method demonstrated a strong correlation with the Spearman's rank correlation coefficient of 0.94, with a mean difference of -2.1 and -7.7 mm/h in the ESR fast detector and Improve® ESR analyzer, respectively. Analysis of the area under the receiver operating curve illustrated a high analytical performance compared to the reference method and CRP level. The measurement of ESR level using the ESR fast detector and Improve® ESR analyzer is a reliable method and has a high analytical performance, which can be used instead of the reference method for screening inflammatory conditions.
Keywords: Analytical performance; C-reactive protein; Westergren method; erythrocyte sediment rate; method validation; modified Westergren method.