Comparison of erythrocyte sedimentation rate by Alifax Roller 20 LC method and standard Westergreen method

Abstract

Erythrocyte sedimentation rate (ESR) is the most common test done for diagnosis and follow up treatment in patients suffering from autoimmune disorders and chronic illness. It is imperative for clinicians to understand the methodology, limitations and variations in testing platforms for ESR from ICSH standardized Westergreen method to various automated testing techniques. We conducted a retrospective study of 150 patients who were tested for ESR using Westergreen method and new automated Alifax Roller 20LC. The data was analyzed by applying Pearsons coefficient of correlation and Bland Altman analysis. It was observed that the automated Alifax Roller 20LC system tends to estimate ESR with positive bias. The maximum agreement between two methods was observed for ESR values between 20-40 mm/hr. As the likelihood of two similar results between two methods is uncertain, the difference between values should be acceptable clinically before replacing the ICSH Westergreen method with any new automated system.

Verification of automatic analysers Roller 20PN and iSED for measuring erythrocyte sedimentation rate

“…Over the last 20 years there were numerous verification and comparison studies of several automated analysers with Westergren method. Several studies have already investigated analytical performances of analysers iSED (Alcor Scientific, Smithfield, SAD) and TEST1 (Alifax S.p.A, Polverara, Italy) ( 5 - 7 ). Analyser TEST1 is widely used for the measurement of ESR, while the newly developed Roller 20PN (Alifax S.p.A, Polverara, Italy) adheres to similar technology but compared to the earlier models has slightly different performance of measuring ESR ( 8 ).…”