Table 4.

Multivariable logistic regression analysis of factors associated with 28-day mortality

Variable	p value	OR (95% CI)
SAPS II score	<0.01	1.08 (1.04–1.23)
SOFA score	≤0.01	1.36 (1.33–1.63)
Double carbapenem treatment	0.02	0.33 (0.13–0.87)

We included all variables in the multivariable logistic regression if they reached p ≤ 0.1 on univariate analysis. A stepwise selection procedure was used to select variables for inclusion in the final model

ROC curve analysis was used to assess the goodness of the final logistic regression model (AUC ± SE = 0.85 ± 0.034 with 95% CI 0.78–0.91; chi-square statistics p < 0.001)

AUC area under the curve, OR odds ratio, ROC receiver operating characteristic, SAPS Simplified Acute Physiology Score, SOFA Sequential Organ Failure Assessment, SE standard error