Pain is subjective though-it is not quantifiable by that number chart, especially for people who don't think in terms of numbers. It would be a lot more accurate to relate a number to something, as
@resonancer just did.
Otherwise, I think you'll get these wildly inconsistent numbers, because sometimes, at the time you experience something-it is the worst. I've had migraines and childbirth and appendicitis (only two of which I went to the hospital for) and I'd list them all as a 9 at the time of the experience (always imagining something could be worse).
Were they really similar on the pain level? Maybe one was an 8, or even would be your 7, but it felt that way at the time, and I still would say 9 for all.
Now, I'm not saying people don't abuse that scale to pretend things are worse than they are, and any medical professional who hears 9 and sees a patient giggling and taking selfies needs to be suspicious. But that scale is growing in importance-it's on every wall near a patient's bed and they have to answer it every time a nurse comes in. Now a hospital doesn't release a patient who had surgery and says they have a pain score of six, so if you want out, you are going to have to say 5. Munchies or druggies may not want out but most of us do. What does a five over a six mean anyway?
Expecting people to accurately differentiate between a 4 or a 6 or a 7 is kinda dumb, not everybody's brain works that way. So you take that number but only as one tiny piece of a puzzle, along with nurse observations, previous hospitalizations, co-morbidities, etc and put a whole picture together then it might be useful. I wonder if it was invented because nobody has time to observe patients anymore?
When people are really in pain, they show it. They can also have pain that is intermittent, so what do you say-where it is now or where it was 15 minutes ago?
Maybe because I'm wordy, but it either hurts like a motherfucker or it's stupid sore ...the difference between 5 or 6 doesn't mean a lot to me, but it's enough to get you released. So it's never more than 4 in my book because hospitals suck.

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