ObjectivesDespite several publications on the analytical performance of high-sensitivity cardiac troponin (hs-cTn) assays, there has been little information on how laboratories should validate and implement these assays into clinical service. Our study provides a practical approach for the validation and implementation of a hs-cTn assay across a large North American City.Design and methodsValidation for the Abbott ARCHITECT hs-cTnI assay (across 5 analyzers) consisted of verification of limit of blank (LoB), precision (i.e., coefficient of variation; CV) testing at the reported limit of detection (LoD) and within and outside the 99th percentile, linearity testing, cTnI versus hs-cTnI patient comparison within and between analyzers (Passing and Bablok and non-parametric analyses). Education, clinical communications, and memorandums were issued in advance to inform all staff across the city as well as a selected reminder the day before live-date to important users. All hospitals switched to the hs-cTnI assay concurrently (the contemporary cTnI assay removed) with laboratory staff instructed to repeat samples previously measured with the contemporary cTnI assay with the hs-cTnI assay only by physician request.ResultsAcross the 5 analyzers and 6 reagent packs the overall LoB was 0.6 ng/L (n=60) with a CV of 33% at an overall mean of 1.2 ng/L (n=60; reported LoD=1.0 ng/L), with linearity demonstrated from 45,005 ng/L to 1.1 ng/L. Precision testing with a normal patient-pool QC material (mean range across 5 analyzers was 3.9–4.4 ng/L) yielded a range of CVs from 7% to 10% (within-run) and CVs from 7% to 18% (between-run) with the high patient-pool QC material (mean range across 5 analyzers was 29.6–36.3 ng/L) yielding a range of CVs from 2% to 5% (within-run) and CVs from 4% to 8% (between-run). There was agreement between hs-cTnI versus cTnI with the patient samples (slope ranges: 0.89–1.03; intercept ranges: 1.9–3.8 ng/L), however, the median CV on patient samples <100 ng/L across the analyzers was 5.6% for hs-cTnI versus 18.7% for the contemporary assay (p<0.001). Following the switch to hs-cTnI testing, no requests for repeat measurements were received.ConclusionsValidation and implementation of hs-cTnI testing across multiple sites requires collaboration within the laboratories and between hospital laboratories and clinical staff.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.