Agreement Among Different Scales for Causality Assessment in Drug-Induced Liver Injury

Background and Objective The causality assessment of drug-induced liver injury (DILI) remains a challenge and eagerly awaits the development of reliable hepatotoxicity biomarkers. None of the different available algorithms used for the causality assessment of DILI has been universally accepted as the gold standard. This study was conducted to examine the agreement among different causality assessment scales in reporting DILI. Methods The World Health Organization-Uppsala Monitoring Center (WHO-UMC), Naranjo, Roussel Uclaf Causality Assessment Method (RUCAM), Maria & Victorino (M & V) and Digestive Disease Week-Japan (DDW-J) assessment scales were used to compare the causalities in all the reported cases of DILI in our adverse drug reaction (ADR) monitoring centre from January 2014 to June 2017. The probability of the causality assessment was classified as 'definite', 'probable', 'possible' and 'unlikely'. The agreement obtained among the causality assessments was analysed using the weighted kappa (kappa(w)) test. Results A total of 33 cases of DILI were included in our analyses. Anti-tubercular therapy (ATT) and methotrexate were the drugs that most commonly caused DILI. The overall agreement among the different scales was poor. The best agreement was found between RUCAM and DDW-J scales (kappa(w): 0.685). Conclusion There were discrepancies among the different causality scales in assessing DILI. This might be due to the different definitions of causality criteria and subjective variability during assessment. A personalised assessment scale incorporating the latest information on specific risk factors and evidence-based criteria for DILI is warranted.