External validation of an admission risk score for predicting inpatient paediatric mortality in two Kenyan public hospitals.

Background: Early identification of children at risk of mortality during hospitalization is crucial in preventing mortality in low-and middle-income countries (LMICs). This study aimed to externally validate an admission risk score for predicting inpatient paediatric mortality in resource-limited settings. Methods: This retrospective study utilized routine clinical data of children aged ≤12 years admitted to two Kenyan public hospitals between January 2017 and October 2023. The admission risk score includes 13 clinical predictors, each assigned a value. Aggregate values were used to predict inpatient pediatric mortality, with a higher score indicating a greater risk of death. Children with scores of 0, 1-4 and ≥5 were categorized as low, moderate and high-risk categories, respectively. Discrimination was assessed using area under the receiver operating characteristic curve (AUC). Sensitivity, specificity, and positive and negative predictive values were calculated at different cutoff points. Results: A total of 15,606 children were included in the study. Majority of the participants were male (8,847, 56.7%) and aged 12 - 59 months (7,222, 46.3%). Children classified as high-risk had a higher mortality rate (23.4%) than those classified as low risk (2%). The risk score demonstrated moderate discrimination, with an AUC of 0.73 (95% confidence interval (CI): 0.71 - 0.75). A cutoff of ≥3 achieved a balance between sensitivity and specificity, with values of 63.8% (95% CI: 60.7%-66.9%) and 72.2% (95% CI: 71.5% - 72.9%), respectively, compared to other cutoff points. Conclusion: The risk score performed moderately in predicting inpatient paediatric mortality in two Kenyan public hospitals. The risk score can be used with other clinical assessments to rapidly identify high-risk children and guide targeted interventions to prevent mortality.