S. Katsaragakis et al., Comparison of Acute Physiology and Chronic Health Evaluation II (APACHE II) and Simplified Acute Physiology Score II (SAPS II) scoring systems in a single Greek intensive care unit, CRIT CARE M, 28(2), 2000, pp. 426-432
Objective: To evaluate Acute Physiology and Chronic Health Evaluation (APAC
HE) II and Simplified Acute Physiology Score (SAPS) II scoring systems in a
single intensive care unit (ICU), independent from the ICUs of the develop
mental sample; and to compare the performance of APACHE II and SAPS II by m
eans of statistical analyses in such a clinical setting.
Design: Prospective, cohort study.
Setting: A single ICU in a Creek university hospital,
Patients: In a time interval of 5 yrs, data for 681 patients admitted to ou
r ICU were collected. The original exclusion criteria of both systems were
employed, Patients <17 yrs of age were dropped from the study to keep compa
tibility with both systems. Eventually, a total of 661 patients were includ
ed in the analysis.
Interventions: Demographics, clinical parameters essential for the calculat
ion of APACHE II and SAPS II scores, and risk of hospital death were record
ed. Patient vital status was followed up to hospital discharge.
Measurements and Main Results: Both systems showed poor calibration and und
erestimated mortality but had good discriminative power, with SAPS II perfo
rming better than APACHE II, The evaluation of uniformity of fit in various
subgroups for both systems confirmed the pattern of underprediction of mor
tality from both models and the better performance of APACHE II over our da
Conclusions: APACHE II and SAPS II failed to predict mortality in a populat
ion sample other than the one used for their development. APACHE II perform
ed better than SAPS II, Validation in such a population is essential, Becau
se there is a great variation in clinical and other patient characteristics
among ICUs, it is doubtful that one system can be validated in all types o
f populations to be used for comparisons among different ICUs.