Validity of diagnoses, procedures, and birth records in a Japanese administrative claims database for pediatric patients

Background Administrative claims data are used in clinical studies; however, recorded diagnoses and procedures have not been fully validated for pediatric patients. We aimed to examine the validity of recorded information on pediatric patients in the Japanese Diagnosis Procedure Combination (DPC) database, a national inpatient database that includes administrative claims data. Methods We validated the DPC data using medical charts as the reference standard. We included patients aged <16 years admitted to a single academic hospital in Tokyo between 2018 and 2022. Positive predictive values were assessed for six diagnoses (cardiac arrest, blood cancer, acute myocarditis, nontraumatic intracranial hemorrhage, hypoplastic left heart syndrome, and trisomy 21) and in‐hospital death. We evaluated intubation, mechanical ventilation, and high‐flow nasal cannulas in 100 randomly selected patients from the neonatal intensive care unit (NICU) and pediatric intensive care unit, and the gestational age and birth weight in NICU patients. Results The positive predictive values of the diagnoses ranged from 70% (non‐traumatic intracranial hemorrhage) to 100% (trisomy 21 and in‐hospital death). The sensitivities of the procedures ranged from 36% (high‐flow nasal cannula in the NICU) to 89% (mechanical ventilation in the NICU), and the specificities were all >95%. The mean gestational ages were 34.2 weeks in the chart and 33.8 weeks in the claims, and the mean birth weights were 2101 g in the chart and 2104 g in the claims, demonstrating high concordance. Conclusion Japanese claims data can be useful for pediatric studies focusing on selected diagnoses, procedures, and birth records with confirmed validity.