X. Castella et al., A COMPARISON OF SEVERITY OF ILLNESS SCORING SYSTEMS FOR INTENSIVE-CARE UNIT PATIENTS - RESULTS OF A MULTICENTER, MULTINATIONAL STUDY, Critical care medicine, 23(8), 1995, pp. 1327-1335
Objective: To compare the performance of three severity of illness sco
ring systems used commonly for intensive care unit (ICU) patients in a
large international data set. The systems analyzed were versions II a
nd III of the Acute Physiology and Chronic Health Evaluation (APACHE)
system, versions I and II of the Simplified Acute Physiology Score (SA
PS), and versions I and II of the Mortality Probability Model (MPM), c
omputed at admission and after 24 hrs in the ICU. Design: A multicente
r, multinational cohort study. Setting: One hundred thirty-seven ICUs
in 12 European and North American countries. Patients: During a 3-mont
h period, 14, 745 patients were consecutively admitted to 137 ICUs enr
olled in the study. Interventions: Collection of information necessary
to compute the APACHE II and APACHE III scores, SAPS I and SAPS II, a
nd MPM I and MPM II scores. Patients were followed until hospital disc
harge. Statistical comparison, including indices of calibration (goodn
ess-of-fit) and discrimination (are!a under the receiver operating cha
racteristic curve). Measurements and Main Results: Despite having acce
ptable receiver operating characteristic areas, the older versions of
the systems analyzed (APACHE II, SAPS, and MPM I computed at admission
-MPM I computed after 24 hrs in the ICU) demonstrated poor calibration
for the whole database. The new versions of the systems (SAPS II and
MPM II) were superior to their older counterparts. This superiority is
reflected by larger receiver operating characteristic areas and bette
r fit. The APACHE III system improved its receiver operating character
istic area compared with the APACHE II system, which showed the best f
it of the old systems analyzed. Conclusions: The new versions of the s
everity systems analyzed (APACHE III, SAPS II, MPM II) perform better
than their older counterparts (APACHE II, SAPS I, and MPM I). APACHE I
I, SAPS II, and MPM II show good discrimination and calibration in thi
s international database.