eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2020-03-28 13 1 79 83 10.13005/bpj/1863 30396 article Tejas A. Acharya 1 Madhav D. Trivedi 1 Krupal J. Joshi 2 Sunita B. Chhaiya 1 Dimple S. Mehta 1 Department of Pharmacology, C. U. Shah Medical College, Surendranagar, India 363001 Department of Community Medicine, C. U. Shah Medical College, Surendranagar, India 363001 Causality assessment is crucial step involved during assessment of Adverse Drug Reactions (ADRs). WHO-UMC causality assessment system and Naranjo algorithm are widely used methods for analysis of ADRs. Study was carried out to evaluate agreement between WHO-UMC causality assessment system and the Naranjo algorithm for causality assessment of ADRs observed in medical ICU of a tertiary care teaching hospital. Causality assessment of all ADRs was done by both WHO-UMC causality assessment system as well as the Naranjo algorithm and classified accordingly. Total 59 ADRs were analyzed. According to WHO-UMC system causal relationship between drug and ADR was certain in 16 ((27.12%), probable in 22 (37.29%), possible in 17 (28.81%), unclassified in 01 (01.69%) and unclassifiable in 03 (05.09%). As per Naranjo algorithm causality was definite in 10 (16.95%), probable in 26 (44.07%) and possible in 23 (38.98%) cases. The agreement between two scales was highest for probable (84.2%) category followed by possible (73.92%) and certain/definite (62.5%) category. on comparing overall agreement between WHO-UMC causality assessment system and Naranjo algorithm using weighted Kappa (κ) test “Moderate” agreement was established (Kappa statistics with 95% confidence interval = 0.60 [0.441,0.758]). For Better evaluation it is recommended to use both the criteria while assessment of causality of ADRs. https://biomedpharmajournal.org/vol13no1/a-study-of-agreement-between-who-umc-causality-assessment-system-and-the-naranjo-algorithm-for-causality-assessment-of-adverse-drug-reactions-observed-in-medical-icu-of-a-tertiary-care-teachi/ Causality Assessment Naranjo Algorithm WHO-UMC System