APPLICATION OF SIX SIGMA METRICS FOR INTERNAL QUALITY CONTROL OF HBV, HCV, AND HIV SCREENING BY ELECTROCHEMILUMINESCENCE AT THE NATIONAL INSTITUTE OF HEMATOLOGY AND BLOOD TRANSFUSION
Main Article Content
Abstract
Background: Serological screening for HBV, HCV, and HIV is essential for blood safety. Traditional Westgard multirules for semi-quantitative assays often yield excessive false rejections and resource waste.
Objectives: To evaluate the analytical performance of ECLIA screening assays for HBV, HCV, and HIV using Six Sigma metrics.
Methods: A retrospective, cross-sectional study analyzed positive internal quality control (IQC) data of HBsAg, anti-HCV, and HIV Ag/Ab assays across five Roche cobas e801 analyzers from July 2023 to December 2024. Allowable Total Error (%TEa) was calculated based on the cut-off distance method. Bias% was estimated against peer-group means via Cobas IT. Sigma values and customized Westgard multirules were determined.
Results: All assays on all five analyzers demonstrated world-class performance Sigma > 6. Consequently, IQC design was simplified to a single 13S rule (N=2) with a run size of 1,000 samples. This strategy reduced out-of-control troubleshooting events by 43.8%, from 32 instances under classic multirules to 18 instances under Westgard-Sigma).
Conclusion: Six Sigma metrics optimize IQC design for blood screening serology, substantially lowering false rejection rates while maintaining high diagnostic reliability.
Keywords
Six Sigma, quality control, blood safety, Westgard Sigma, cobas e801
Article Details
References
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