Why is the definition of “event” defined as any “adverse event?
The agency does not have a formal definition of “event”. An “event” is simply an outcome. Any outcome that an individual, whether a health care provider or consumer, believes may have resulted from an administration of a vaccine, may be reported to VAERS. Any such report will be entered into the system, whether or not there appears to be a causal relation to the vaccine. Thus, there can be no precise definition of “event,” since the reporters are the ones who determine what is reported.
