An adverse event that is medically significant but not life-threatening; or for which inpatient care or prolongation of hospitalization are indicated; or that is an important medical event that does not result in hospitalization, but may jeopardize the patient or may require intervention either to prevent hospitalization, to prevent the AE from becoming life-threatening or causing death; or that is disabling; or that results in persistent or significant disability, incapacity, or limitation of self care activities of daily living (ADLs, e.g., getting in and out of bed, dressing, eating, getting around inside, bathing, or using the toilet). [from
NCI]