Patient safety events are categorized based on their occurrence and impact. A near-miss event is one where a potential error is identified and corrected before it reaches the patient, preventing harm.

Option A (An adverse event): An adverse event is an incident that results in harm to the patient. Since the medication was not administered, no harm occurred, so this is not an adverse event.

Option B (A near-miss event): This is the correct answer. A near-miss event occurs when an error (e.g., incorrect dose ordered due to wrong weight) is identified and corrected before it affects the patient. NAHQ CPHQ study materials define near-misses as opportunities to improve systems and prevent future errors, emphasizing their importance in safety reporting.

Option C (A sentinel event): A sentinel event is a serious, unexpected event resulting in death or significant harm (e.g., wrong-site surgery). Since no harm occurred, this does not qualify as a sentinel event.

Option D (A never event): Never events are serious, preventable errors (e.g., surgery on the wrong patient) that should never occur. This incident, while serious, was caught before administration and does not meet the criteria for a never event.