Table 1.
Luminex® and EllaTM multiplex platforms: dynamic range and limits of quantification for biomarkers of severe infection.
Fig 1.
Intra-assay variability for biomarker concentrations determined using the Luminex® and EllaTM platforms.
Coefficient of variance (CV%) values for 156 sample assayed in duplicate by the Luminex® platform (shaded circles) and for 406–410 samples assayed by internal triplicate by the EllaTM platform (open triangles). Analysis for sICAM-1 was excluded due to inappropriate dilution range. Graphs depict point estimates of the mean CV% and the corresponding 95% confidence intervals.
Fig 2.
Relationship between raw untransformed concentration values obtained by the Luminex® compared to the EllaTM platform.
Spearman’s rho correlation coefficient (ρ) and p-values obtained using Spearman rank correlation for values (n) within assay dynamic range of both platforms.
Table 2.
Correlation between Luminex® and EllaTM platform concentrations in pg/mL.
Fig 3.
Bland-Altman plots comparing agreement between biomarker concentrations determined using the Luminex® and EllaTM platforms.
Upper and lower limits of agreement (dotted black lines) correspond to 2 standard deviations (SD) away from the mean difference (dashed black line). P-values represent Pitman's test of difference in variance, with a non-significant value indicating no variance across the range of mean values determined by both platforms. Analyses were performed on Loge-transformed biomarker concentrations that were within assay dynamic range of both platforms (summarized in Table 2).
Table 3.
Bland-Altman bias representing difference in Loge-transformed biomarker concentrations computed by Luminex® compared to the EllaTM platform for values within dynamic range of both assays.