Concordance, Variance, and Outliers in 4 Contemporary Cardiac Troponin Assays: Implications for Harmonization

摘要: BACKGROUND: Data to standardize and harmonize the differences between cardiac troponin assays are needed support their universal status in diagnosis of myocardial infarction. We characterized variation methods, comparability 99th-percentile cutoff thresholds, occurrence outliers 4 assays. METHODS: Cardiac was measured duplicate 2358 patient samples on platforms: Abbott Architect i2000SR, Beckman Coulter Access2, Roche Cobas e601, Siemens ADVIA Centaur XP. RESULTS: The observed total variances 3 I (cTnI) methods cTnI T (cTnT) were larger than expected from analytical imprecision (3.0%–3.7%). between-method variations 26% 127% cTnT dominant contributors variances. misclassification results according 99th percentile 3%–4% 15%–17% cTnT. assay identified 49% more as positive cTnI. Outliers detected 1 (0.06%) with Abbott, 8 (0.45%) Coulter, 10 (0.56%) Roche, (0.17%) Siemens. CONCLUSIONS: definition infarction should not depend choice analyte or analyzer, between- within-method described here need be considered application this respect. that cannot explained by discordant classification respective percentiles addressed.