Adverse event

Background

• Any untoward medical occurrence in a patient or research participant who is receiving a treatment
• Does not necessarily have a causal relationship with the treatment
• Adverse events that have at least a possible relationship with the treatment are called adverse reactions
• A serious adverse event is also known as a serious adverse drug reaction

Grading

Common Terminology Criteria for Adverse Events (CTCAE)

Grade	Description
Grade 1	Mild; asymptomatic or mild symptoms; clinical or diagnostic observations only; intervention not indicated
Grade 2	Moderate; minimal, local or non-invasive intervention indicated; limiting age-appropriate instrumental Activities of Daily Living.
Grade 3	Severe or medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated; disabling; limiting self-care ADL
Grade 4	Life-threatening consequences; urgent intervention indicated
Grade 5	Death related to AE