Which of the following is NOT considered a type of adverse event?

In the context of healthcare, adverse events are typically categorized into different types based on their severity and impact on patient safety. Catastrophic, minor, and major events are all classifications of adverse events, as they relate to incidents that can cause harm to patients, affecting their health care outcomes.

An accidental event, while it can lead to an adverse event, does not inherently categorize itself as an adverse event on its own. It is often better described as a cause or occurrence that may lead to an adverse event, rather than a classification of the event itself. Therefore, it is understood that among the various classifications of adverse events, "accidental" does not fit into that framework of severity classification like the others do. Thus, recognizing that "accidental" is not itself a recognized type of adverse event clarifies why it is the correct choice in this context.