Management of vitamin K antagonists (VKA) is difficult, and overdoses can have dramatic hemorrhagic consequences. These works form part of a European computerized medical data processing project, which aims to develop IT tools for describing adverse drug events (ADEs).

Materials and methods A tool enabling retrospective research of potential ADE cases was developed, using complex ADE detection rules taking into account chronological parameters: the ADE scorecards. The rules were applied on 14,748 medical records from a community hospital. We evaluated the predictive positive value of the rules related to INR elevation by an expert review of the detected cases. The severity of the clinical consequences was evaluated.

Results 49 cases were detected, among which 11 cases were ADEs. The predictive positive value of the rules is 22.44%, mostly related to antibiotics and amiodarone introduction. The four cases of clinical damage related to a drug were properly designated by the rules.

Discussion – Conclusion Our study shows the great potential of developing complex rules for the identification of adverse drug events in large medical databases.