Performance of Pediatric Risk of Mortality, Pediatric Index of Mortality and PIM2 in term Chinese neonates

Abstract

Pediatric Risk of Mortality (PRISM), Pediatric Index of Mortality (PIM) and PIM2 could be applicable to the subset of term neonates has not been well investigated. The purpose of this study is to access and compare the performance of these scoring systems in predicting mortality probability in term Chinese neonates with critical illness. PRISM, PIM and PIM2 scores were calculated prospectively during a 1-year period on 243 neonates admitted to the neonatal intensive care unit (NICU) in the Children's Hospital of Zhejiang University in China. Of these, 36 neonates (14.81%) died in the NICU, while the mortality rates estimated by PRISM, PIM and PIM2 were 16.19, 14.58 and 11.12%, respectively. The area under the receiver-operating characteristic (ROC) curve [95% confidence intervals (CIs)] were 0.834 (0.767-0.902), 0.851 (0.786-0.916) and 0.854 (0.790-0.918) for PRISM, PIM and PIM2, respectively. The Hosmer-Lemeshow test gave a chi-square of 1.35 (p = 0.930) for PRISM, 1.03 (p = 0.960) for PIM and 4.58 (p = 0.469) for PIM2. The standardized mortality rates (SMRs) (95% CI) using PRISM, PIM and PIM2 were 0.92 (0.79-1.08), 1.02 (0.88-1.20) and 1.33 (1.13-1.62), respectively. Although PRISM, PIM and PIM2 have displayed good discrimination and calibration in the present setting, PIM is considered as the most accurate and appropriate tool for predicting mortality in the studied NICU.