DBT
Contributor
It seems to me that if two people report that their pain on a scale from 1 to 10 was 5 then it means exactly the same thing. That's because the subjective experience of pain is relative to past experience. That said, the scale is usually relative to the context of the situation and to the amount of pain that can be reasonably expected, but also to what amount of pain is willing to be accepted (such as when a dentist asks how much pain the patient is feeling and whether to administer more anesthetic).
Two people reporting a pain level of 5 may not be the same if we had an objective meter of pain, say set at a universal average of 5, because some are more sensitive to pain than other, even individual pain thresholds vary over time. It's not a fixed value.