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Agreement between WHO-UMC causality scale and the Naranjo algorithm for causality assessment of adverse drug
Ajay K Shukla1, Ratinder Jhaj1, Saurav Misra1
1Department of Pharmacology, AIIMS Bhopal, Madhya Pradesh, India.
Background:
The Pharmacovigilance Program of India recommends the use of the World Health Organization-Uppsala Monitoring Centre (WHO-UMC) scale, while many clinicians prefer the Naranjo algorithm for its simplicity. In the present study, we assessed agreement between the two widely used causality assessment scales, that is, the WHO-UMC criteria and the Naranjo algorithm.
Materials And Methods:
In this study, 842 individual case safety reports were randomly selected from 1000 spontaneously reported forms submitted to the ADR Monitoring Center at a tertiary healthcare Institute in Central India between 2016 and 2018. Two well-trained independent groups performed the causality assessment. One group performed a causality assessment of the 842 ADRs using the WHO-UMC criteria and the other group performed the same using the Naranjo algorithm. The agreement between two ADR causality scales was assessed using the weighted kappa (κ) test.
Results:
Cohen's kappa coefficient (κ) statistical test was applied between the two scales (WHO-UMC scale and Naranjo algorithm) to find out the agreement between these two scales. "No" agreement was found between the two scales {Kappa statistic with 95% confidence interval = 0.048 (P < 0.001)}.
Conclusion:
There was no agreement found between the WHO-UMC criteria and the Naranjo algorithm in our study.
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