I think the point stands, since that test is reliant on a patient reporting a sensation of pain. In the same way, psychiatrists must rely on patients expression the emotional problem they're feeling.

Reading that wiki entry, it looks like any objective measurements that arose from dolorimeters are not in active use, because they weren't helpful.

This is a systematized way to elicit a subjective report. My original point stands; we cannot measure it objectively (if, indeed, there is even merit to such a concept).