Comparison of newer scoring systems with the conventional scoring systems in general intensive care population

Abstract

Background: The aim of this study was to assess the performance of Acute Physiology and Chronic Health Evaluation (APACHE) IV, Simplified Acute Physiology Score (SAPS) III, and Mortality Probability Model (MPM) III0 and compare these systems to more widely validated prognosis prediction tools like APACHE II, III, SAPS II, MPM II0 and Sequential Organ Failure Assessment (SOFA) score.

Methods: The study provided a retrospective analysis of data for all consecutive patients admitted to a medical ICU over a 15-month period. Data related to patient demographics, and that necessary to compute various scores were recorded. Calibration was assessed by calculating Lemeshow-Hosmer goodness-of-fit test. Discrimination was evaluated by calculating the area under curves (AUC). Primary outcome measure was Intensive Care Unit mortality.

Results: Mortality predicted by APACHE IV score was closest to that of actual mortality with a SMR of 0.868 followed by that of MPM III0 (0.794) and SAPS III (0.763) scores. APACHE III (χ2=3.674), with P=0.885 had the best calibration followed by APACHE II (χ2=7.959; P=0.438) and SOFA scores (χ2=8.369; P=0.301). All scores had good efficacy and even though there was no significant difference between AUCs of various scores, MPM III0 (0.947) performed the best followed by APACHE IV (0.928) and MPM II0 (0.928).

Conclusion: Overall, the newer scoring systems performed better than their older counterparts and were more accurate. Nevertheless, the difference in efficacy was not statistically significant and the choice of scoring system may depend on the ease of use and local preferences.