Differences in adverse drug events and medication errors among pediatric inpatients aged <3 and ≥3 years: The JADE study

Background Adverse drug events (ADEs) are defined as any injuries due to medication use. We hypothesized that the incidences of ADEs and medication errors (MEs) could be associated with linguistic skills of pediatric patients. Methods We analyzed data from the Japan Adverse Drug Events study on pediatric inpatients. This study included inpatients aged one months and older and less than seven years old. We compared the primary outcome of ADEs and MEs between patients aged under three years and three years and older as children typically do not acquire sufficient linguistic skills until around three years of age. Results This study included 639 patients; 412 (64%) patients aged under three years and 227 (36%) patients aged three years and older. We identified 241 ADEs in 639 patients; 152 ADEs among patients aged under three years (37 ADEs per 100 patients) and 89 ADEs among those aged three years and older (39 ADEs per 100 patients). ADEs among patients aged under three years were less likely to be found (49 ADEs) during their hospital stay than those aged three years and older (20 ADEs) (P = 0.02). Among 172 MEs identified in 639 patients, 25 MEs (15%) resulted in ADEs; 23 (92%) occurred to those aged under three years and two (8%) occurred to those aged three years and older (P = 0.0008). Conclusion ADEs were less likely to be found and MEs resulted in ADEs more frequently in patients under three years old, and these differences could be explained by differences in their linguistic skill levels.