Abusive Head Trauma (AHT) is a leading cause of morbidity and mortality in infants requiring rapid neuroimaging performance and prognostic rapid diagnosis. The Pittsburgh Infant Brain Injury Score (PIBIS) clinical prediction rule (CPR) was derived to identify infants most likely to present brain injury, whose diagnosis would benefit from head CT. Our study aimed to externally validate the PIBIS CPR in a pediatric French population.

A retrospective study was conducted in a French pediatric emergency department between 2015 and 2017. We included all consecutive infants who underwent a neurological imaging. Medical data were collected, and PIBIS score was determined, both retrospectively.

We included 129 infants among which 33 cases (including 20 with a diagnosis of AHT). The sensitivity and specificity of the PIBIS CPR were 75.8 % (95 % CI 57.7-88.9) and 61.4 % (51.0-71.2) and negative and positive predictive values 88.1 % (77.8-94.7) and 40.3 % (33.0-48.2). Among the 20 infants with a diagnosis of AHT, 19 (95.0 %) were correctly identified by the PIBIS CPR.

Our external validation study found a lower diagnostic value of the PIBIS CPR than in the original study. This argues for adding biomarkers to improve its performance, notably in the context of suspected AHT.