Which scenario would automatically meet the criterion of having a mechanism of injury?

• A. An adult with a mild headache and no injury
• B. A person with a motor-vehicle collision mechanism of injury
• C. A person who denies illness
• D. A person who is well and claims to be well

Answer: (B)

Mechanism of injury means the event or force that caused potential harm. A motor-vehicle collision is an explicit event that transfers energy to the body, so it automatically meets the criterion for having a mechanism of injury, even if the person currently has no obvious injuries. The other scenarios describe symptoms or health status without describing any event that could cause injury, so they do not establish a MOI. In EMS, recognizing MOI helps flag potential trauma and guides assessment and transport decisions.