Completeness of spontaneously reported adverse drug reactions in 4 databases

Aims To assess the completeness of information provided in adverse drug reaction (ADR) reports in 4 spontaneous report databases. Methods The study was conducted using freely accessible ADR reports from the Canada Vigilance Adverse Reaction Online Database, the US Food and Drug Administration Adverse Event Reporting System (FAERS) database, the UK Yellow Card Scheme and the Danish Medicines Agency ADR Database, covering the period 2014–2023. The variables used to evaluate the completeness of ADR reports were selected based on the vigiGrade completeness tool. Descriptive statistics were used to report the completeness of information in each ADR report, while chi‐square tests were used to analyse differences in completeness by seriousness of report. Results In total, 290 079 individual case safety reports were analysed: 4289 from the Canadian database; 269 763 from the FAERS database; 13 624 from the UK Yellow Card Scheme; and 2403 from the Danish database. The most frequently completed information was the primary reporter, with nearly 100% completeness. The most frequently omitted information was the route of administration, with completion scores of 44% in the UK Yellow Card Scheme, 55% in the Danish database and 58% in the Canadian database. In FAERS, the event date was the most frequently omitted information with a completeness rate of 50%. Conclusion The completeness of information varied across different variables, with information frequently omitted for route of administration and event date. Enhancing awareness about providing complete information during ADR reporting is essential for collecting complete data and allowing signal detection.