... design, analysis of results, interpretation of findings, and drafting of the paper.Independent statistical analysis. The accuracy of the data analysis was inde-pendently verified by William Shannon, ... proportional hazardsassumption was validated for each model.Statistical Analysis Software version 9.1.3 (SAS Insti-tute, Inc., Cary, NC, USA) was used for statistical analy-ses. P values less than ... wasassociated with statistically significant shorter dura-tions of mechanical ventilation (median, 7 versus 10days) and hospitalization (median, 22 versus 26 days)than was use of comparator antibiotics...