> 99.9% of people won't ever get colon cancer, and therefore won't ever benefit from a colonoscopy. But they may have complications from a colonoscopy, that's

> 99.9% of people won't ever get colon cancer, and therefore won't ever benefit from a colonoscopy. But they may have complications from a colonoscopy, that's the idea. No test is completely harmless, even a blood work. You save some lives but may loose others, that's the point of the paper. And of course you waste resources that can be used to find a cure.