Causality assessment of adverse events reported to the Vaccine Adverse Event Reporting System (VAERS).

Unlabelled: Adverse events following immunization (AEFI) reported to the national Vaccine Adverse Event Reporting System (VAERS) represent true causally related events, as well as events that are temporally, but not necessarily causally related to vaccine.

Objective: We sought to determine if the causal relationships between the vaccine and the AEFI reported to VAERS could be assessed through expert review.

Design: A stratified random sample of 100 VAERS reports received in 2004 contained 13 fatal cases, 19 cases with non-fatal disabilities, 39 other serious non-fatal cases and 29 non-serious cases.