FOUR-Based Modification of ICU Severity Scores

The goal of this observational study is to evaluate whether the Full Outline of UnResponsiveness (FOUR) score can replace the Glasgow Coma Scale (GCS) as the neurologic component of established intensive care unit (ICU) severity scoring systems and to derive and validate modified APACHE, SAPS, MODS, LODS, and SOFA models incorporating the FOUR score in critically ill adult patients. The main questions it aims to answer are: Does replacing the GCS with the FOUR score provide comparable or improved discrimination for in-hospital mortality across established ICU severity scoring systems? Can FOUR-based modifications of APACHE, SAPS, MODS, LODS, and SOFA be successfully derived and validated with adequate discrimination, calibration, and overall predictive performance? Do the modified FOUR-based models demonstrate predictive performance comparable to or different from the corresponding original GCS-based models? Researchers will compare the performance of the modified FOUR-based models with their original GCS-based counterparts to determine whether substitution of the FOUR score provides valid and clinically useful risk prediction in critically ill adults. Participants will not receive an experimental intervention. Data routinely collected during ICU care will be used to: Calculate the original GCS-based APACHE, SAPS, MODS, LODS, and SOFA scores. Replace the GCS component with the FOUR score and derive the corresponding modified models. Evaluate and validate the predictive performance of the original and modified models using measures of discrimination, calibration, and overall predictive accuracy.