Related Experiment Videos
A comparison of three scoring systems for mortality risk among retrieved intensive care patients
1Department of Paediatric Intensive Care, Guy's Hospital, London, UK. shane.tibby@gstt.sthames.nhs.uk
Insights
The Pediatric Index of Mortality (PIM) score demonstrated better data collection and less impact from retrieval processes compared to pre-ICU Pediatric Risk of Mortality (PRISM) and PRISM II. Recalibration is needed for all pediatric intensive care unit mortality scoring systems.
Area of Science:
- Pediatric intensive care
- Clinical scoring systems
- Mortality risk assessment
Background:
- Paediatric intensive care unit (PICU) retrieval teams are crucial for transferring critically ill children.
- Evaluating the performance of mortality risk scoring systems in retrieved PICU patients is essential.
Purpose of the Study:
- To assess the impact of two PICU retrieval teams on three mortality risk scoring systems: pre-ICU PRISM, PIM, and PRISM II.
- To compare the performance and data completeness of these scoring systems.
Main Methods:
- A total of 928 critically ill children retrieved for intensive care were studied.
- Performance metrics including discrimination (area under the ROC curve) and calibration were assessed.
- Data completeness for each scoring system was evaluated.
Main Results:
- Risk stratification was similar between retrieval teams for pre-ICU PRISM and PIM, despite case mix differences.
- PIM had the highest data completeness (88%) compared to pre-ICU PRISM (24%) and PRISM II (60%).
- All scoring systems showed good discrimination (AUC 0.83-0.87) but suboptimal calibration, with over-prediction in medium risk bands. PIM showed better discrimination for respiratory disease.
Conclusions:
- PIM offers advantages due to less impact from the retrieval process and easier data collection.
- All assessed scoring systems require recalibration for optimal performance in retrieved pediatric intensive care populations.
Aims:
To assess the impact of two paediatric intensive care unit retrieval teams on the performance of three mortality risk scoring systems: pre-ICU PRISM, PIM, and PRISM II.
Methods:
A total of 928 critically ill children retrieved for intensive care from district general hospitals in the south east of England (crude mortality 7.8%) were studied.
Results:
Risk stratification was similar between the two retrieval teams for scores utilising data primarily prior to ICU admission (pre-ICU PRISM, PIM), despite differences in case mix. The fewer variables required for calculation of PIM resulted in complete data collection in 88% of patients, compared to pre-ICU PRISM (24%) and PRISM II (60%). Overall, all scoring systems discriminated well between survival and non-survival (area under receiver operating characteristic curve 0.83-0.87), with no differences between the two hospitals. There was a tendency towards better discrimination in all scores for children compared to infants and neonates, and a poor discrimination for respiratory disease using pre-ICU PRISM and PRISM II but not PIM. All showed suboptimal calibration, primarily as a consequence of mortality over prediction among the medium (10-30%) mortality risk bands.
Conclusions:
PIM appears to offer advantages over the other two scores in terms of being less affected by the retrieval process and easier to collect. Recalibration of all scoring systems is needed.