Clinical application of a new method for determination of the erythrocyte sedimentation rate using the BC-720 automated hematology analyzer

Background: The erythrocyte sedimentation rate (ESR) is a nonspecific inflammatory indicator and is widely used in clinical diagnosis. Westergren is the gold standard method recommended by the International Committee for Standardization of Hematology (ICSH), but it is time-consuming and inconvenient and has biosafety risks. A new alternate method for ESR (Easy-W ESR) measurement was designed and integrated into the Mindray BC-720 series automated hematology analyzer to meet the clinical needs of hematology laboratories for efficiency, safety, and automation. In this study, the performance of the new ESR method was evaluated based on the ICSH recommendations on modified and alternate ESR methods.Methods: Methodological comparisons using the BC-720 analyzer, TEST 1, and the Westergren method were performed to assess repeatability, carryover, sample stability, reference range validation, factors influencing the ESR, and clinical applicability in rheumatology and orthopedics.Results: The correlation between the BC-720 analyzer and the Westergren method was good (Y = 2.082 + 0.9869X, r = 0.9657, P > 0.0001, n = 342), carryover was < 1%, the repeatability standard deviation was <= 1 mm/h, and the coefficient of variation (CV) was <= 5%. The reference range meets the manufacturer's claim. For rheumatology patients, the BC-720 analyzer showed a good correlation with the Westergren method (Y = 1.021X-1.941, r = 0.9467, n = 149). For orthopedic patients, the BC-720 analyzer also showed a good correlation with the Westergren method (Y = 1.037X + 0.981, r = 0.978, n = 97).Conclusion: This study verified the clinical and analytical performance of the new ESR method, indicating that the results are very similar to those obtained using the Westergren method.