What is Pharmacovigilance?
According to the WHO-- it is defined as the science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other drug-related problem.
What is Causality Assessment?
When a patient on a drug develops a new symptoms or sign, the key question clinician ask is- did the drug cause this? Answering it is rarely straightforward. The event might be-- because of the underlying disease, a concomitant medicine, or a true drug reaction.
Causality assessment - evaluating the relationship between a medicine and an adverse event to see whether the medicine actually caused it or happened due to some other reasons.
Major Causality Assessment scale:
1.WHO-UMC system – Used in the VigiBase international spontaneous reporting database. it is qualitative and algorithm-free, rely on the clinical judgment guided by the standardised criteria for each category.
2.Naranjo Algorithm (Naranjo scale) – was proposed by Dr. Claudia A. Naranjo and his colleagues from the University of Toronto in the year of 1981.
this is a 10-question probabilistic questionnaire- that assign a numerical score which is to estimate the probability of an ADR. it was specifically developed to standardize the assessment of causality for all ADRs.
Other scales include-
RUCAM- gold standard for drug-induced liver injury (DILI).
Jones/Kramer-decision-tree based.
LCAT-structured, flow diagram-based tool-assessing ADRs in clinical setting.
