B-113 Beckman Coulter DxI 9000 immunoassay analyzer assay performance meets new CLIA 2024 performance goals with highest proportion of Six Sigma performance amongst all major manufacturers

Abstract Background The Clinical Laboratory Improvement Act (CLIA) proficiency testing (PT) criteria will be updated in July 2024 with some goals tightening by up to 40%. It is assumed, but not known, that all assays and instruments will be able to achieve these goals. Using these new CLIA 2024 goals, estimates of current instrument group performance from an international proficiency testing (PT) survey have shown significant differences in quality, calling into question which assays can achieve the new CLIA goals. Currently, the highest performing diagnostic instrument achieves only 35.2% 6-Sigma, while the majority of instruments have less than 15% 6-Sigma performance indicating a higher probability of future PT failures. Methods Eighteen assays that will be governed by new CLIA 2024 goals were assessed for Sigma metric performance on the DxI 9000 immunoassay analyzer: Alpha Fetoprotein (AFP), Beta hCG, Carcinoembryonic antigen (CEA), Cortisol, Creatine Kinase MB (CK-MB), Estradiol, Ferritin, Folate, Follicle-Stimulating Hormone (FSH), Prolactin, Para-thyroid hormone (PTH), Total Prostate specific antigen (Total PSA), Testosterone, Thyroid Stimulating Hormone (TSH), Total Triiodothyronine (TT3),high sensitivity Troponin I, Total Thyroxine (TT4) and Vitamin B12. Precision and bias were determined following CLSI EP5 and EP9 guidelines, measured across 3 reagent lots. CLIA 2024 PT criteria provides the allowable total error for the standard Sigma-metric calculation: Sigma-metric = (TEa - |bias|) / SD Performance of the other major analyzers was assessed using the methodology introduced in 2006 by Westgard JO and Westgard SA. The Sigma-metric predicts future problems with PT and potential optimization of QC procedure opportunities, including fewer Westgard Rules, control levels, even reduced QC frequency and materials leading to less cost and time saved. Results Half (50%) of the assays on DxI 9000 achieves 6-Sigma, outperforming all other major manufacturers in the market who range from only 5% to 35% 6-Sigma. Further, over 78% of the DxI 9000 performance was 4Sigma and higher. Less than 8% of performance fell below 3-Sigma, which was observed at the extreme ends of the reportable range. Conclusions The DxI 9000 assay performance is well designed to meet CLIA 2024’s new PT criteria and has the highest prevalence of 6-sigma assay performance observed on market when compared to the top 5 major instrument manufacturers. Assays with Sigma metrics at 4-Sigma and higher are unlikely to face analytical PT difficulties and can be optimized for reduced Westgard Rules, control levels, and potentially even QC frequency.