Do you think colic is a real ailment?

Anybody who has had a truly colicky baby will say it is real. I know my niece was colicky. Nothing was wrong with her, no reflux and she was a good eater but she would just scream and scream and scream. They ran tests and found nothing. The thing about colic is that it is a baby that isn't easy to comfort for whatever reason. Usually the washing machine spin cycle or the vacuum cleaner for whatever reason helps calm them down. It is just like with SIDS (unidentifiable deaths in an infant where they can find no known causes). It is a label just so they know something is going on but can't find out what.