Variables included in this multivariate analysis with bootstrapped stepwise selection were simultaneously statistically significant at a p-value <0.10 in the univariate analysis and clinically relevant, i.e. easily available upon admission to the intensive care unit (ICU) (delay since malignancy, first-line chemotherapy as status of malignancy, bone marrow transplantation, lobar acute respiratory distress syndrome (ARDS) on computed tomography, Simplified Acute Physiology Score II score on day one, and use of antibiotic active on difficult-to-treat (DTT) bacteria at ICU admission).