SOFA-2 versus SOFA-1 for mortality prediction in critically ill patients

Abstract

We validated the SOFA-2 score against the SOFA-1 score using 65,366 critically ill patients from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. SOFA-2 demonstrated superior discrimination for ICU mortality (AUROC: 0.829 [95% CI 0.823–0.835] vs. 0.796 [0.789–0.803]) and in-hospital mortality (0.789 [0.783–0.794] vs. 0.763 [0.757–0.769]) compared with SOFA-1. Of 65,366 patients, 40,990 (62.7%) were reclassified to higher scores under SOFA-2. Within each SOFA-1 stratum, those assigned higher SOFA-2 scores consistently demonstrated higher ICU mortality, confirming clinically meaningful reclassification. These findings provide additional external validation supporting the advantages of SOFA-2 for risk stratification in critically ill patients.