EuroSCORE-II and POSPOM in Cardiac Surgery

We aim to compare the performances of the European System for Cardiac Operative Risk Evaluation (EuroSCORE-II) and the PreOperative Score to Predict Postoperative Mortality (POSPOM) in predicting in-hospital mortality among patients undergoing on-pump cardiac surgery, with further evaluation of discrimination, calibration, agreement, and clinical utility. This retrospective observational study will be conducted at a single tertiary university cardiac surgery centre. Adult patients (≥18 years) who underwent coronary artery bypass grafting, valve surgery, or combined procedures between 2020 and 2024 will be included. No experimental interventions will be applied. Preoperative EuroSCORE-II and POSPOM values will be calculated for all patients. Discrimination will be assessed using ROC and precision-recall curves with DeLong's test. Calibration will be evaluated using calibration-in-the-large, calibration slope, Hosmer-Lemeshow testing, and GiViTI calibration belts. Agreement will be analyzed using ICC, CCC, Bland-Altman plots, and Passing-Bablok and Deming regression. Subgroup analyses will be performed by age and sex.