I was going to mention the white-coat effect, but couldn't place what it was called. Once- keyword 'once'- a few years ago, I had abnormally high blood pressure; fortunately it was only during an ER visit for something entirely unrelated, so they didn't pay attention and didn't know my BP has always been on the low/normal side. Cause: I'd been eating a large amount of black licorice, and had no idea it raises BP. I was glad I noticed it instead of them, or they probably would have hauled out the prescription pad. In general, though, it's often too much like that old t.v. show "House"- 'We really don't know what the person has, so we'll start treating him/her for something, maybe we'll be correct, maybe not."