The Nurse Is Working at a Pain Clinic and Is

The nurse is working at a pain clinic and is preparing an orientation for new staff nurses. Which definition of pain should the nurse include in the orientation?

A) Pain is validated after determining the cause.
B) Pain is an unpleasant sensation, typically experienced upon movement.
C) Pain is whatever the experiencing person says it is.
D) Pain is very subjective, so observation must be used to assess the characteristics.