A question sent to Doctor D:
"Why do doctors ask for information that has nothing to do with what I'll be seen about?"
Doctor D asks his patients superfluous questions all the time. You come to Doctor D with ankle pain and next thing you know you are answering questions about your breathing, how much alcohol you drink, if you have fevers, and your sex life. Doctor D asks these questions because he is nosy.
Doctors are nosy, but the more pertinent reason we must ask those questions is because we are lazy. Doctors, like most people, have a nasty habit of jumping to conclusions before thinking carefully. To combat mental laziness the MD powers-that-be came up with the "Review of Systems" where doctors ask a whole lot of questions about your body that don't directly relate to what's bothering you. It forces your doctor to think outside the box. Usually it turns out to be the obvious diagnosis, but the Review of Systems helps your doctor recognize when it isn't.
Doctors also do this because we are greedy: insurance won't pay for your exam unless at least some Review of Systems is done. Fortunately this is one of those situations where your insurance company actually does something for your benefit. They know a Review of Systems is cheaper than a CT Scan.
When you come to Doctor D with a swollen ankle without any injury it is probably gout. But questions about your breathing or your genitals force Doctor D to at least consider that non-traumatic ankle swelling can be caused by a blood clot or a gonorrhea infection.
So now you'll know why we ask all those crazy questions.
Ah, the glamorous life of an MD!
