The vertical axis reports the different rapid tests challenged. The horizontal axis reflects the odds ratio magnitude using IDEXX® HerdCheck BSE-scrapie short protocol as reference test. Panels A, B, C, D (left column) report the results obtained under the w/v protocol; panels E, F, G, H (right column) display the results under the manufacturers' instructions. BSE forms studied: panels A, E: strong C-type; panels B, F: weak C-type; panels C, G: H-type; panels D, H: L-type. All the weak C type water dilutions series tested negative with Bio-Rad® TeSeE™ SAP (notably, the optical densities were for all the three replicates of the 1∶2 dilution just under the cut-off value), thereby, the odd ratio could not be calculated (Subfigure B).