Assessment of severity and avoidability of adverse drug reactions in neonates: a reproducibility study of the Hartwig tool and LAAT

Tools for classifying adverse drug reactions (ADRs) have not yet been validated in the context of the neonatal intensive care unit (NICU). The study aims to investigate the inter-rater reliability of the Hartwig tool and the Liverpool avoidability assessment tool (LAAT) in assessing the severity and avoidability of ADR cases in hospitalized neonates.

An observational and prospective study was conducted in the NICU of a maternity hospital in Natal, Brazil. The Hartwig tool and LAAT were employed to assess the severity and avoidability of ADRs, respectively. Three experienced clinical pharmacists independently assessed all ADR cases. Inter-rater reliability was measured using Cohen’s kappa coefficient (k) with corresponding 95% confidence intervals (CI).

Among 79 ADR cases, the mean gestational age was 29.7 ± 4.4 weeks, and the birth weight averaged 1446.0 ± 1179.3 g. The assessment of ADR severity using the Hartwig tool revealed a significant overall correlation (overall k = 0.573; 95% CI 0.395 to 0.753) with exact agreement (EA) and extreme disagreement (ED) rates between evaluators of 86.5% and 2.5%, respectively. However, no statistically significant correlation was observed for determining avoidability using the LAAT (overall k = 0.017; 95% CI − 0.048 to 0.082), with an EA rate of 83.6% and ED rate of 10.1%.

The Hartwig tool demonstrates good reproducibility among different evaluators in determining the severity of ADRs, unlike the LAAT for assessing avoidability.