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Ann Melvin, MD
Associate Program Director, Research Subject Advocate Program

Office: CHRMC W-7871
Mailstop W-6605
(206) 987-2535
ann.melvin@seattlechildrens.org

Adverse Events: Definition and Grading

Adverse Event An Adverse Event is any unfavorable and unintended sign (including an abnormal laboratory finding), symptom or disease temporally associated with the use of a medical treatment or procedure regardless of whether it is considered related to the medical treatment or procedure. This includes all deaths that occur while a subject is on a study.

Adverse Event Grade Definition
Serious Any adverse event occurring at any dose that results in any of the following outcomes: death, a life-threatening adverse event (see below), requires inpatient hospitalization or prolongation of existing hospitalization, a persistent or significant disability/incapacity, or a congenital anomaly/birth defect.

Important medical events that may not result in the previous outcomes may be considered a serious adverse drug experience when, based upon appropriate medical judgment, they may jeopardize the patient or subject and may require medical or surgical intervention to prevent one of the outcomes listed in this definition.
*Life-threatening An experience that in the opinion of the Investigator places the subject at immediate risk of death from the reaction as it occurred, i.e., it does not include a reaction that, had it occurred in a more severe form, might have caused death.
Other Any adverse experience that does not meet the definition of serious. Non-serious adverse experiences can be classified as:
Mild An experience that is usually transient, & requires no special treatment or intervention. The experience does not generally interfere with usual daily activities. Includes transient laboratory test alterations
Moderate An experience that is alleviated with simple therapeutic treatments. The experience impacts usual daily activities. Includes laboratory test alterations indicating injury, but without long-term risk.
Severe An experience that requires therapeutic intervention. The experience interrupts usual daily activities. If hospitalization is required for treatment it becomes a serious adverse event.

Unexpected/Expected Adverse Drug Events:

Event Grade Definition
Unexpected Any adverse experience, the nature, severity or frequency of which is not consistent with the current investigator brochure; or with the risk information described in the investigational plan or protocol or consent form. Unexpected refers to an experience that has not been previously observed. This includes events that are more serious than expected or occur more frequently than expected.
Expected Those experiences that have been identified in nature, severity, or frequency in the current investigator brochure, investigational plan/protocol and current consent form.
top | Site Credits NCRR Funded under NCRR Grant M01-RR-00037 Updated: 03/02/2006 11:41 AM
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