Reportable range of quantitative assays for SARS-CoV-2 antibodies determination. An overlooked issue?

In order to identify the quantization capability of two methods for SARS-CoV-2 IgG determination (Anti-SARS-CoV-2 QuantiVac ELISA IgG from Euroimmun and SARS-CoV-2 IgG anti-RBD from SNIBE), the linearity of the reportable range with respect to the calibration curve was evaluated.