PRAGMATIC ASSESSMENT OF THREE CAUSALITY ASSESSMENT SCALES FOR REPORTING ADVERSE DRUG REACTIONS: A PROSPECTIVE AND RETROSPECTIVE ANALYSIS

Ms. Kalpana Purohit, Dr. Bhomik Goel, Dr. Yusra Ahmed, Dr. Ravi Kant and Dr. Puneet Dhamija*

ABSTRACT

Objective: Causality assessment is an integral part of reporting of adverse drug reactions. This assessment is done at all the steps of evaluation of adverse effects. The time and resources available for causality assessment are different at different levels which affects the process. Additionally, there is no universally accepted measure for causality assessment presently. Methods: Three scales of causality assessment of Adverse Drug Reaction (ADR) namely WHO, Naranjo and Karch & Lasagna scales were compared for agreement of causality categories and time consumed to assign categories to 500 ADR detected retrospectively and prospectively. Results: The findings of present study demonstrated a good agreement between WHO and Karch and Lasagna scale (k = 0.93) rather than between WHO and Naranjo scales (k = 0.78). Time consumed for assigning categories was least with Karch and Lasagna scale and maximum with Naranjo Scale. Conclusion: The results of present study propose the site specific use of scale for causality assessment of ADR. Karch and Lasagna scale can be used in resource poor settings like out-patient department and for preliminary assessment while WHO and Naranjo scale can be used in resource intensive settings. Training of physicians, pharmacovigilance associates in periphery and those based at coordination centres should be customised accordingly.

Keywords: ADR, Karch and Lasagna scale.