Wells M, Riera-Fanego J F, Luyt D K, Dance M, Lipman J
Department of Anesthesia, Baragwanath Hospital, Johannesburg, South Africa.
Crit Care Med. 1996 Sep;24(9):1507-13. doi: 10.1097/00003246-199609000-00013.
The use of the Pediatric Risk of Mortality (PRISM) score or other scoring systems in the intensive care unit (ICU) is of great importance for evaluating the efficacy and efficiency of a particular ICU. However, the PRISM score was developed and validated in the United States and subsequently validated in Europe, but has not been evaluated in a less affluent society. In general, scoring systems should be used only in populations similar to the reference population in which the prediction model was developed. We set out to determine the applicability of the PRISM score at Baragwanath Hospital, South Africa.
Prospective, descriptive study.
Twenty-four-bed multidisciplinary ICU.
We analyzed 1,528 consecutive pediatric admissions from January 1989 to June 1994.
None.
PRISM scores, Therapeutic Intervention Scoring System scores, demographic, and clinical data collected prospectively were entered and stored by means of a commercial software package at the time of admission of each patient. The prediction of actual mortality by PRISM scoring was evaluated by the Hosmer and Lemeshow goodness-of-fit test (chi2[8 degrees of freedom]). Receiver operating characteristic curves were constructed and compared with those curves from pediatric ICU populations in the United States and Europe. Individual receiver operating characteristic curves were constructed for surgical and nonsurgical patients, age categories, and diagnostic categories. Compared with European and American ICU populations, our patients were younger, were mostly nonsurgical emergency admissions, stayed longer in the ICU, and were more severely ill with a higher admission PRISM score and overall mortality rate. Respiratory and septic diagnoses predominated, with very few surgical cases admitted. The Hosmer and Lemeshow goodness-of-fit test showed a significant failure of the PRISM scoring system to accurately predict mortality over a wide range of expected mortality rates (chi2[8 degrees of freedom] = 465, p = 0). Similarly, receiver operating characteristic analysis indicated a poor predictive power (Az = 0.73 +/- 0.01 [SEM]), with an area under the curve significantly less than that for the PRISM reference population (p = 0). PRISM showed equally poor discriminatory function at all age groups and diagnostic categories.
The PRISM score needs to be recalibrated or recalculated for our patient population in view of the high discrepancy and poor discriminatory function shown. Part of the inaccuracy may derive from different demographic characteristics of our ICU population and a different pattern of diseases. It appears that PRISM is not population independent.
在重症监护病房（ICU）中使用儿童死亡风险（PRISM）评分或其他评分系统对于评估特定ICU的疗效和效率非常重要。然而，PRISM评分是在美国开发并验证的，随后在欧洲也得到了验证，但尚未在较不富裕的社会中进行评估。一般来说，评分系统应该只用于与开发预测模型时的参考人群相似的人群。我们着手确定PRISM评分在南非巴拉干纳特医院的适用性。
前瞻性描述性研究。
拥有24张床位的多学科ICU。
我们分析了1989年1月至1994年6月期间连续收治的1528例儿科患者。
无。
在每位患者入院时，通过商业软件包输入并存储前瞻性收集的PRISM评分、治疗干预评分系统评分、人口统计学和临床数据。通过Hosmer和Lemeshow拟合优度检验（自由度为8的卡方检验）评估PRISM评分对实际死亡率的预测。构建受试者工作特征曲线，并与美国和欧洲儿科ICU人群的曲线进行比较。为手术和非手术患者、年龄类别和诊断类别构建个体受试者工作特征曲线。与欧美ICU人群相比，我们的患者年龄更小，大多是非手术急诊入院患者，在ICU停留时间更长，病情更严重，入院时PRISM评分更高，总体死亡率也更高。呼吸和败血症诊断占主导地位，手术病例很少。Hosmer和Lemeshow拟合优度检验显示，PRISM评分系统在广泛的预期死亡率范围内未能准确预测死亡率（自由度为8的卡方检验=465，p = 0）。同样，受试者工作特征分析表明预测能力较差（Az = 0.73±0.01[标准误]），曲线下面积明显小于PRISM参考人群（p = 0）。PRISM在所有年龄组和诊断类别中的鉴别功能同样较差。
鉴于所显示的高度差异和较差的鉴别功能，PRISM评分需要针对我们的患者群体进行重新校准或重新计算。部分不准确可能源于我们ICU人群不同的人口统计学特征和不同的疾病模式。看来PRISM并非与人群无关。
