Prieto Espuñes S, López-Herce Cid J, Rey Galán C, Medina Villanueva A, Concha Torre A, Martínez Camblor P
Unidad de Cuidados Intensivos Pediátricos, Hospital Universitario Central de Asturias, Universidad de Oviedo, Asturias, España.
An Pediatr (Barc). 2007 Apr;66(4):345-50. doi: 10.1157/13101237.
To assess the validity of the Pediatric Risk of Mortality score (PRISM), the Pediatric Index of Mortality (PIM) and the PIM 2 in two Spanish pediatric intensive care units.
We prospectively studied 241 critically ill children consecutively admitted over a 6-month period. The overall performance of the scoring systems was assessed by the Standardized Mortality Ratio (SMR), comparing observed deaths with expected deaths by each index. Discrimination (the ability of the model to distinguish between patients who live and those who die) was quantified by calculating the area under the receiver operating characteristic (ROC) curve. Calibration (the accuracy of mortality risk predictions) was calculated with the Hosmer-Lemeshow goodness-of-fit test, in which statistical calibration is evidenced by p > 0.05.
The mortality rate was 4.1 %. PRISM overestimated mortality (SMR = 0.44). Discrimination was better for PRISM and PIM 2 than for PIM (areas under ROC curves: 0.883, 0.871, and 0.800 respectively), with no significant differences. Finally, calibration was acceptable for PIM 2 (x2 (8) = 4.8730, p 0.8461) and for PIM (x2 (8) = 8.0876, p 0.5174), but no statistical calibration was found for PRISM (x2 (8) = 15.0281, p 0.0133).
PIM and PIM 2 showed better discrimination and calibration than PRISM in a heterogeneous group of children in Spanish critical care units. However, these results should be confirmed in a larger study.
评估小儿死亡风险评分（PRISM）、小儿死亡率指数（PIM）及PIM 2在西班牙两个儿科重症监护病房中的有效性。
我们对连续6个月内收治的241名危重症儿童进行了前瞻性研究。通过标准化死亡率（SMR）评估评分系统的整体表现，将各指数观察到的死亡人数与预期死亡人数进行比较。通过计算受试者工作特征（ROC）曲线下面积来量化区分能力（模型区分存活患者和死亡患者的能力）。使用Hosmer-Lemeshow拟合优度检验计算校准度（死亡风险预测的准确性），其中p>0.05表明具有统计学校准。
死亡率为4.1%。PRISM高估了死亡率（SMR=0.44）。PRISM和PIM 2的区分能力优于PIM（ROC曲线下面积分别为：0.883、0.871和0.800），差异无统计学意义。最后，PIM 2（χ2(8)=4.8730，p=0.8461）和PIM（χ2(8)=8.0876，p=0.5174）的校准度可接受，但PRISM未发现统计学校准（χ2(8)=15.0281，p=0.0133）。
在西班牙重症监护病房的一组异质性儿童中，PIM和PIM 2的区分能力和校准度优于PRISM。然而，这些结果应在更大规模的研究中得到证实。
