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Understanding harm

How harm occurs

"Adverse event" terminology

An adverse event refers to harm resulting from healthcare delivery [REF]
Canadian Patient Safety Institute, Disclosure Working Group. Canadian Disclosure Guidelines, 2008.

This includes harm from the recognized risks inherent in investigations or treatments, system failures, and sometimes problems in provider performance. Combinations of these factors may occur. While system failures contribute to many adverse events, the performance of a provider may also be a contributing factor in some adverse events.

To learn more about "adverse event" terminology, click on each box in the diagram.
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or combination
  • Harm

    • Underlying medical condition/disease

    • Adverse event

      • Inherent risks of investigations or treatments

      • System failures

      • Individual provider performance


An outcome that negatively affects the patient's health or quality of life. It may result from the underlying medical condition or an adverse event, or a combination of these factors.