Joshua E Raizman1, Albert K Y Tsui2, Bobbi-Lynn Goudreau3, Anna K Füzéry2, Mathew Estey4, Hossein Sadrzadeh5, Trefor Higgins2. 1. Alberta Precision Laboratories, North Sector, Edmonton, Alberta, Canada; Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, Alberta, Canada. Electronic address: josh.raizman@albertaprecisionlabs.ca. 2. Alberta Precision Laboratories, North Sector, Edmonton, Alberta, Canada; Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, Alberta, Canada. 3. Alberta Precision Laboratories, North Sector, Edmonton, Alberta, Canada. 4. Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, Alberta, Canada; DynaLIFE Medical Labs, Edmonton, Alberta, Canada. 5. Department of Pathology & Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada; Alberta Precision Laboratories, South Sector, Calgary, Alberta, Canada.
Abstract
OBJECTIVES: Previous analytical evaluations of the Beckman Coulter Access high sensitivity troponin (hsTn) I assay have focused on single platforms and laboratory sites. The purpose of this study was to determine assay robustness across different platforms at multiple sites, platform-specific characteristics, and equivalence to other hsTn methods in a large laboratory network. METHODS: Barricor plasma was used to assess imprecision, linearity, sensitivity (limit of blank and detection, LOB/LOD), and comparability to the conventional AccuTnI+3 and other hsTn assays. Various studies were conducted across a total of 9 laboratories using Beckman DxI800 and Access2 platforms. RESULTS: Within-laboratory precision was <10% across all target patient pool concentrations, however, DxI800 mean values were 20% higher than Access2 in the range of 3.6-44.9 ng/L. LOBs and LODs were lower on DxI800, 0.27 and 0.90 ng/L, respectively, compared to 2.9 and 3.2 ng/L, on Access2. Both showed excellent linearity across the full range. In method comparison to AccuTnI+3, DxI800 had a higher slope (0.9417 versus 0.8495) and positive bias (+18.1% versus -9.9%) compared to Access2, a trend further pronounced at concentrations <150 ng/L. At values <150 ng/L, there was good agreement with Abbott hsTnI (slope = 1.017, r = 0.932), but poor agreement with the Roche hsTnT assay (slope = 1.687, r = 0.589). Inter-laboratory split sample comparisons across 2 DxI800 and 7 Access2 sites showed close agreement, except at low concentrations <10 ng/L where DxI800 was 2.8 ng/L higher (p<0.001). CONCLUSIONS: The Beckman hsTnI assay showed robust analytical performance across different laboratories and platforms. However, discrepancies between platforms were found at low concentrations where rapid acute myocardial infarction (AMI) rule-out decisions occur. These differences have important implications for AMI risk assessment, suggesting that laboratories should develop platform-specific parameters rather than using them interchangibly.
OBJECTIVES: Previous analytical evaluations of the Beckman Coulter Access high sensitivity troponin (hsTn) I assay have focused on single platforms and laboratory sites. The purpose of this study was to determine assay robustness across different platforms at multiple sites, platform-specific characteristics, and equivalence to other hsTn methods in a large laboratory network. METHODS: Barricor plasma was used to assess imprecision, linearity, sensitivity (limit of blank and detection, LOB/LOD), and comparability to the conventional AccuTnI+3 and other hsTn assays. Various studies were conducted across a total of 9 laboratories using Beckman DxI800 and Access2 platforms. RESULTS: Within-laboratory precision was <10% across all target patient pool concentrations, however, DxI800 mean values were 20% higher than Access2 in the range of 3.6-44.9 ng/L. LOBs and LODs were lower on DxI800, 0.27 and 0.90 ng/L, respectively, compared to 2.9 and 3.2 ng/L, on Access2. Both showed excellent linearity across the full range. In method comparison to AccuTnI+3, DxI800 had a higher slope (0.9417 versus 0.8495) and positive bias (+18.1% versus -9.9%) compared to Access2, a trend further pronounced at concentrations <150 ng/L. At values <150 ng/L, there was good agreement with Abbott hsTnI (slope = 1.017, r = 0.932), but poor agreement with the Roche hsTnT assay (slope = 1.687, r = 0.589). Inter-laboratory split sample comparisons across 2 DxI800 and 7 Access2 sites showed close agreement, except at low concentrations <10 ng/L where DxI800 was 2.8 ng/L higher (p<0.001). CONCLUSIONS: The Beckman hsTnI assay showed robust analytical performance across different laboratories and platforms. However, discrepancies between platforms were found at low concentrations where rapid acute myocardial infarction (AMI) rule-out decisions occur. These differences have important implications for AMI risk assessment, suggesting that laboratories should develop platform-specific parameters rather than using them interchangibly.