Figure 6.

Comparative analysis of our assay with the gold standard E-test. (A) EC₈₀ values of our assay are plotted against the MIC values of E-test to evaluate the essential agreement of our assay. The diagonal of the plot represents 100% agreement between EC₈₀ and the E-test MIC. The region between dash lines is ± one two-fold dilution of variation from the diagonal of the plot, indicating essential agreement between EC₈₀ and MIC. The data points outside the range of essential agreement are marked in red. Our assay’s essential agreement of with E-test is 85.7%. (B) Categorical antimicrobial susceptibility R (Resistant), I (Intermediate), or S (Susceptible) was determined using the CLSI reference. Our assay’s categorical interpretation is plotted against E-test’s interpretation. The green boxes in the diagonal of the plot indicate 100% category agreement between EC₈₀ and MIC. Minor discrepancy is defined if E-test result is R or S and our EC₈₀ result is I, or the E-test result is I and our EC₈₀ result is R or S. Major discrepancy is defined if the E-test result is S and our EC₈₀ result is R; very major discrepancy is defined if E-test result is R and our EC₈₀ result is S. Only 4.8% of minor discrepancy (3 out of 21 strain/antimicrobial combinations) and no major or very major discrepancies were observed.