TABLE 3.

Results from CART and univariate logistic regression analyses to determine which pharmacodynamic indices significantly predicted clinical and microbiological response and the associated breakpoint for predicted success

Response category and parameterCART analysis resultLogistic regression
% Breakpointa% Response rate (above, below)POdds ratio (95% CI)P
Clinical
    % fT > MIC2487.4, 1001.01.0 (0.001-2.83)0.970
    fCmax/MIC30292.3, 80.60.1092.90 (0.85-10.54)0.090
    fCmin/MIC592.8, 78.10.0483.58 (1.05-13.13)0.043
    fAUC/MIC1,18992.5, 79.40.0993.22 (0.94-11.04)0.064
Microbiological
    % fT > MIC5488.6, 57.10.055.85 (1.14-30.03)0.034
    fCmax/MIC38393.1, 75.70.0294.34 (1.23-15.34)0.023
    fCmin/MIC592.3, 73.30.0224.36 (1.32-15.82)0.018
    fAUC/MIC6,35596.8, 81.30.0546.92 (0.86-55.9)0.070
  • a Percentages of error for misclassification of clinical success during CART were 70.8%, 44.9%, 28.1%, and 28.1% for percent fT > MIC, fCmax/MIC, fCmin/MIC, and fAUC/MIC breakpoints, respectively. Percentages of error for misclassification of microbiological success during CART were 8.5%, 46.3%, 61.0%, and 57.3% for %fT > MIC, fCmax/MIC, fCmin/MIC, and fAUC/MIC breakpoints, respectively.