Comparison of Outcomes using Pediatric Index of Mortality (PIM) -3 and PIM-2 Models in a Pediatric Intensive Care Unit

ABSTRACT

Objectives: To compare patient outcomes using the Pediatric Index of Mortality-3 (PIM-3)model with PIM-2 model for children admitted to the intensive care unit. Methods: Weprospectively recorded the baseline characteristics, variables of PIM-3 and PIM-2 atadmission, and outcomes of children ?17 years over a period of 11 months. We used AreaUnder Receiver Operating Characteristics (AU-ROC) curves and Goodness-of-fit (GOF)tests to determine which of the two models had better discrimination and calibration.Results: Out of 202 children enrolled, 69 (34%) died. Sepsis and pneumonia were thecommon admitting diagnoses. The AU-ROC was better for PIM-3 (0.75) as compared to PIM-2 (0.69; P=0.001). The GOF-P value was 0.001 for both models, that indicated poorcalibration of both (P<0.001). The AU-ROC curves were acceptable across different age anddiagnostic sub-groups. Conclusion: PIM-3 had better discrimination when compared toPIM-2 in our unit. Both models had poor calibration across deciles of risk.