Statistical evaluation of positive to negative cutoff ratio. The BCKG ratio is the OD ratio of buffer applied to ELISA wells relative to that of NHS (100-fold dilution) applied to carbonate buffer-coated wells. The NHS ratio is the OD ratio of NHS (100-fold dilution) applied to DCLHb-coated wells relative to that of NHS applied to carbonate buffer-coated wells. The monkey serum ratios are the OD ratios of monkey serum (at different dilution factors) applied to DCLHb-coated wells relative to that of NHS applied to carbonate buffer-coated wells. The lower tolerance limit for the positive DCLHb antibody (monkey serum) and upper tolerance for the negative DCLHb antibody responses are shown. The displayed data are the results from all analyses (including those having multiple analysts, assays, plates, etc).