External Validation of Six Pediatric Fever and Neutropenia Clinical Decision Rules

Background: Fever and neutropenia (FN) clinical decision rules (CDRs) are recommended to help distinguish children with cancer at high and low risk of severe infection. The aim of this study was to validate existing pediatric FN CDRs designed to stratify children with cancer at high or low risk of serious infection or medical complication. Methods: Pediatric CDRs suitable for validation were identified from a literature search. Relevant data were extracted from an existing data set of 650 retrospective FN episodes in children with cancer. The sensitivity and specificity of each of the CDR were compared with the derivation studies to assess reproducibility. Results: Six CDRs were identified for validation: 2 were designed to predict bacteremia and 4 to predict adverse events. Five CDRs exhibited reproducibility in our cohort. A rule predicting bacteremia had the highest sensitivity (100%; 95% confidence interval (CI): 93%-100%) although poor specificity (17%), with only 15% identified as low risk. For adverse events, the highest sensitivity achieved was 84% (95% CI: 75%-90%), with specificity of 29% and 27% identified as low risk. A rule intended for application after a 24-hour period of inpatient observation yielded a sensitivity of 80% (95% CI: 73-86) and specificity of 46%, with 44% identified as low risk. Conclusions: Five CDRs were reproducible, although not all can be recommended for implementation because of either inadequate sensitivity or failure to identify a clinically meaningful number of low-risk patients. The 24-hour rule arguably exhibits the best balance between sensitivity and specificity in our population.