BACKGROUND: The aim of this study was to determine which of the most commonly used scoring systems for evaluation of critically ill patients in the ICU is the best and simplest to use in our hospital.

MATERIAL AND METHODS: This prospective study included 60 critically ill patients. After admittance to the ICU, APACHE II, SAPS II, and MPM II0 were calculated. During further treatment in the ICU, SOFA and MPM II were calculated at 24 h, 48 h, and 72 h and 7 days after admittance using laboratory and radiological measures.

RESULTS: In comparison with survivors, non-survivors were older (p<0.01) and spent significantly more days on mechanical ventilation (p<0.01). ARDS was significantly more common in patients who survived compared to those who did not (chi-square=7.02, p<0.01), which is not the case with sepsis (chi-square=0.388, p=0.53). AUROC SAPS II was 0.690, and is only slightly higher than the other 2 AUROC incipient scoring systems, MPM II and APACHE II (0.654 and 0.623). The APACHE II has the highest specificity (81.8%) and MPM II the highest sensitivity (85.2%). MPM II7day AUROC (1.0) shows the best discrimination between patients who survived and those who did not. MPM II48 (0.836), SOFA72 (0.821) and MPM II72 (0.817) also had good discrimination scores.

CONCLUSIONS: APACHE II and SAPS II measured on admission to the ICU were significant predictors of complications. MPM II7day has the best discriminatory power, followed by SOFA7day and MPM II48. MPM II7day has the best calibration followed by SOFA7day and APACHE II.

Keywords: APACHE, Calibration, Critical Care - standards, Critical Illness, Intensive Care Units, Models, Statistical, Prospective Studies, ROC Curve, Reproducibility of Results, Respiration, Artificial, Risk, Severity of Illness Index