The Health Interview Survey, conducted by the National Center for Health Statistics, asks respondents:
“Now, I’d like to read you a short list of different kinds of pain. Please say for each one, on roughly how many days–if any–in the last 12 months you have had that type of pain…How many days in the last year have you had headaches?”
The question is then repeated for backaches, stomach pains, joint pains, muscle pains, and dental pains.
I don’t think I could answer that question. Seems to me we’re asking people for things that they can’t tell us.