From Quora: My Answer to "Is it possible to do worse on an standardized test (take, for example, the SAT) by being sick (varying from the common cold to a stomach sickness) on that day?"
Yes. Anything that distracts you from the test will cause problems. A cold probably won’t affect you much, but a stomach virus that’s making you have to get up and go to the bathroom every few minutes will seriously reduce your time, and thus your score.
No standardized test will give you extra time for any reason, including illness, a car accident on the way, and in one story I’ve heard about the California Bar Exam, a test-taker actually reviving another test taker who had a heart attack during the test!
If you’re really sick on test day, I would suggest you just not show up, and contact the College Board BEFORE test time to let them know why. I believe the SAT and ACT people will let you reschedule tests if you let them know before test time, but I’m not 100% certain how far in advance you have to reschedule to avoid losing your whole test fee and having to re-pay for the test. See this link to get the official College Board information on this topic. Changing Your Registration Information
In any event, the fee is NOT the main consideration here. If you are sick with a contagious illness on test day, please don’t go and infect others just because you “need” to take the test. That’s one reason to schedule the test BEFORE the last possible date you can take it and meet admissions deadlines. Also, if you know you’re really sick after the test starts, you can “cancel” your scores. See here - Canceling Scores
Hope this helps!
Author: John Linneball Who did you think? ;-)
I'm the proprietor and only tutor for this business; that's why I named it after me.