calling a test the ‘Empathy Quotient’ does not, on its own, make it a test of empathising. Asking people to report on their own social sensitivity is a bit like testing mathematical ability with questions like I can easily solve differential equations, or assessing motor skills by asking people to agree or disagree with statements like I can pick up new sports very quickly. There’s something doubtfully subjective about the approach.
The counterargument here is that empathy is internal so it would be hard for an observer to know whether you *really* cared about someone else's pain, or whether you were pretending to.