Causality assessment of suspected adverse drug reactions: A transatlantic view

The European Community's (EC) pending requirement for a standard assessment of the causal association between a drug product and a reported drug-associated event prompts a review of this aspect of pharmaceutical safety evaluation. Pharmaceutical manufacturers who use various methods, or no methods, may need to consider these EC definitions and their interpretation for evaluating their current procedures and planning any future changes. This paper first describes the EC classifications and their basis as one statement on the status of causality assessment in Europe. Reflecting the rather different view of causality assessment in North America, this paper then briefly reviews the evolution and uses of causality assessment over the last two decades. The controversies over causality are next discussed, followed by examination of the diverse uses of assessment by a pharmaceutical manufacturer or a regulator. Finally, the paper concludes with thoughts on applying causality concepts as tools for enhancing drug-risk assessment.