An assessment of reported adverse drug reactions in a Tertiary Care Hospital in South India: A retrospective cross‑sectional study

Objectives: The primary objective of this study was to assess the causality of ADRs using World Health Organization‑Uppsala Monitoring Centre (WHO–UMC), Naranjo and Liverpool ADR Causality Assessment Tool (LCAT). Other primary objective was to assess the agreement between the WHO‑UMC criterion, Naranjo algorithm and LCAT. The secondary objective was to assess the reported adverse drug reactions in a tertiary care hospital in South India. Materials and Methods: This was a cross‑sectional retrospective study. All the ADRs which were reported by the Pharmacovigilance Unit between July 2016 and March 2017 were assessed. Causality assessment was performed by two well‑trained independent pharmacologists by applying the three methods–WHO, Naranjo and LCAT. Concurrence between the two algorithms was compared using the Cohen’s weighted kappa statistic. Results: Causality assessment of adverse reactions according to Naranjo criteria shows that 81% cases were of probable type, 9.5% cases were possible and 9.5% cases were unlikely. Causality assessment of adverse reactions according to WHO‑UMC criteria shows that 85.7% cases were of probable type, 4.8% cases were possible, 4.8% cases were unlikely and 4.8% cases were definite. Causality assessment of adverse reactions according to Liverpool criteria shows that 61.9% cases were of probable type, 4.8% cases were possible and 33.3% cases were definite. Cohen’s kappa test shows that negative and poor concurrence was seen between WHO and Naranjo causality comparison (κ = −0.161). Positive but poor concurrence based on kappa values was seen between Liverpool and Naranjo’s causality comparison (κ = 0.133). Negative and poor concurrence based on kappa values was seen between WHO and Liverpool causality comparison (κ = −0.161). Conclusion: The most frequent causality category observed by the WHO‑UMC criteria, Naranjo as well as the Liverpool algorithm was “Probable.” Full concurrence was not found between any of two scales of causality assessment.