A-003 Beckman Coulter DxI 9000 Immunoassay Analyzer’s High Sensitivity Troponin I achieves 90% six sigma performance when assessed against clia 2024 performance goals

Abstract Background In July 2024, the Clinical Laboratory Improvement Act (CLIA) proficiency testing (PT) criteria will directly regulate Troponin I performance for the very first time. The new CLIA goal is 0.9 ng/mL or 30%, whichever is greater. CAP previously set a goal of 30% or 3 times the group standard deviation (SD), whichever is greater, a more permissive setting. Estimates of current instrument group performance from an international proficiency testing (PT) survey have shown none of the 5 major diagnostic instruments can achieve the biological minimum goal at a 6-Sigma level, while 4 of the 5 instruments perform at 3 Sigma or below. Performance of these platforms was assessed using the methodology introduced in 2006 by Westgard JO and Westgard SA. The DxI 9000 high sensitivity Troponin I assay was assessed to determine if it could achieve the new CLIA 2024 goals. Methods The DxI 9000 high sensitivity Troponin I assay was assessed with three reagent lots, on both serum and Lithium Heparin (LiHep) samples, following Clinical Laboratory Standards Institute (CLSI) protocols EP05 and EP09 to estimate imprecision and bias. The new CLIA 2024 PT criteria supplied the allowable total error for the standard Sigma-metric calculation: Sigma-metric = (TEa - |bias|) / SD The Sigma-metric predicts not only future problems with PT, but also potential optimization of QC procedures, including fewer Westgard Rules, control levels, even reduced QC frequency which can lead to less cost, time, and materials. Results The majority (91.7%) of data points across the analytical measuring range for DxI 9000’s high sensitivity Troponin I assay from both serum and LiHep samples achieved 6-Sigma performance. For serum, only 8.3% of samples achieved 5-sigma performance. For LiHep, only 4.2% of the performance was 4 Sigma. None of the performance was 3 Sigma or lower. Conclusions The superior precision observed on DxI 9000 high sensitivity Troponin I delivers overwhelming 6-sigma performance when assessed by CLIA’s 2024 goal. This assay is highly unlikely to face PT difficulties and can be optimized for reduced Westgard Rules, reduced control levels leading to a reduction in time, materials, and cost.