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Table 3 Adverse events classification

From: Evaluation of the immunogenicity and safety of different doses and formulations of a broad spectrum influenza vaccine (FLU-v) developed by SEEK: study protocol for a single-center, randomized, double-blind and placebo-controlled clinical phase IIb trial

Adverse event intensity
 Mild An event that is easily tolerated by the subject, causing minimal discomfort and not interfering with everyday activities
 Moderate An event that causes sufficient discomfort as to interfere with normal everyday activities
 Severe An event that prevents normal everyday activities
 Serious Any untoward medical occurrence that:
o Results in death
o Is life threating (an event in which the subject was at risk of death at the time of the event)
o Requires hospitalization or prolongation of an existing hospitalization
o Results in disability or permanent damage as defined as a substantial disruption of a person’s ability to conduct normal life functions
o Is a congenital anomaly/birth defect
o Other adverse events that may jeopardize the subject or may require medical or surgical intervention to prevent one of the other outcomes
Adverse event causality
 Unrelated Where an event is not considered related to the investigational medicinal product
 Unlikely Although the relationship to investigational medicinal product cannot be completely ruled out, the nature of the event, the underlying disease, concomitant medication or temporal relationship make other explanations more likely
 Possibly related The temporal relationship and the absence of a more likely explanation suggest the event could be related to the investigational medicinal product
 Probably related The known effects of the investigational medicinal product or its therapeutic class, or based on challenge testing, suggest the investigational medicinal product is the most likely cause
 Definitely related This category applies to those AEs that are clearly a consequence of administration of the drug. It is likely that such events will be widely documented and generally accepted as having association with the study medication.