Analytical characteristics of the NeuMoDx™ SARS-CoV-2 assay and clinical agreement with the BD MAX system

Accurate and automated molecular detection of SARS-CoV-2 has played an important role in routine clinical diagnostics and laboratory workflow management. This study evaluated the analytical characteristics of the NeuMoDx™ SARS-CoV-2 assay and compared its clinical detection performance with the BD MAX SARS-CoV-2 system. Analytical performance was assessed using AccuPlex™ SARS-CoV-2 reference materials for dilutional response, reproducibility, and analytical sensitivity evaluation, whereas clinical performance was evaluated using 84 nasopharyngeal swab specimens. The NeuMoDx™ assay demonstrated strong correlations between Ct values and viral RNA concentrations, with R² values of 0.9971 and 0.9952 for the N and Nsp2 targets, respectively. Intra-run precision showed low variability, with standard deviations of 0.23 and 0.34 at 500 copies/mL for the N and Nsp2 targets, respectively. Under the experimental conditions of this study, detectable amplification signals were observed at concentrations as low as 50 copies/mL using reference materials. Clinical comparison demonstrated a positive percent agreement (PPA) of 97.3% and a negative percent agreement (NPA) of 100% between the two systems. Positive specimens exhibited Ct values ranging from approximately 20-35. In pooling experiments, detectable amplification signals were observed at a dilution ratio of 1:5 using a representative specimen with a Ct value of approximately 30, although detection consistency decreased at higher dilution ratios. These findings provide additional analytical performance data for an automated SARS-CoV-2 molecular diagnostic platform and contribute to the evaluation of automated PCR-based testing workflows.