Fig. 4: Assessment of inter-assay (within-laboratory) variability for samples tested in PBNA. | npj Vaccines

Fig. 4: Assessment of inter-assay (within-laboratory) variability for samples tested in PBNA.

From: WHO International Standards for antibodies to HPV6 HPV11 HPV31 HPV33 HPV45 HPV52 and HPV58

Fig. 4

Ratios of maximum and minimum laboratory estimates of HPV antibody concentration (un-transformed) for samples tested in at least 3 independent PBNA. A greater than 4-fold difference (blue dashed line cut-off) in sample antibody concentrations across assays was selected as a guideline to identify greater inter-assay variability.

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