Assessment of suitability of pediatric index of mortality 2 score for monitoring the outcome of pediatric intensive care unit patients and associated risk factors of mortality in a tertiary care center in South India
Keywords:PIM 2 score, Discrimination, Calibration, SMR
Background: Pediatric index of mortality 2 (PIM 2) score is an illness severity and scoring systems used for predicting outcome of children admitted to PICU. The objective was to evaluate the usefulness of PIM 2 score in predicting mortality in our PICU, assess whether the model is calibrated to our case mix and to compare the observed and expected death rates by calculating standardised mortality ratio.
Methods: It was a prospective observational study done in a tertiary care center from January 2019 to June 2020. Consecutive 120 patients admitted to PICU aged from 1 month to 18 years were enrolled in study. PIM 2 scoring was calculated for the data obtained within 1 hour of admission to PICU. The outcome was recorded as death or discharge. PIM 2 logit score is calculated using software.
Results: PIM2 can discriminate between death and survival with area under curve (AUC) of 0.867 with 95% CI (0.729,0.980). PIM 2 predicted death rate was significant (p<0.001). The model is well calibrated with Hosmer- Lemeshow Goodness-of-fit test p=0.961 (p>0.05). The observed death rates are equal to predicted death rates and standardized mortality ratio (SMR) is equal to 1.
Conclusions: PIM 2 score predicted mortality correlated well with observed mortality in PICU patients. The model is well calibrated for use in our set up and discriminate well between survivors and non-survivors.
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