Quantity vs Sensitivity

Hello, Question about what to consider a quantity and what a sensitivity. I quote VIM 3 2007:

1.1 (1.1) quantity property of a phenomenon, body, or substance, where the property has a magnitude that can be expressed as a number and a reference

4.12 (5.10) sensitivity of a measuring system sensitivity quotient of the change in an indication of a measuring system and the corresponding change in a value of a quantity being measured

If the measurand is a sensitivity, for example in the vibration field. Should I consider the Quantity a sensitivity? Shouldnt there be an element for the sensitivity?

Thanks Diego