Number of adverse event ratings required for true probability of adverse event to exceed 50%, 75%, and 95%.

This table enables the identification of the number of raters required to obtain a given certainty that a case ‘truly’ represents an adverse event. For example, if an investigator wished to be 95% certain a case represented an adverse event, then it would be necessary to have a minimum of three reviewers and all three would need to agree. With only two reviewers, once could be at best 75% certain a case represented an adverse event.