Dr. Levi Prevention is an interesting term. Most people would agree it’s a good thing.  If someone says, “take an asprin a day to prevent  heart attacks by 50%,” that sounds good. “Get a mammogram to prevent dying from breast cancer”.  People do it.  Besides, who wants to die from something that’s preventable? No one! But, how do you prove you prevented a disease? Ah, there’s the rub. It turns out that its not a very scientific process. Say someone gets the flu shot for 20 years and never gets the flu. They may say “the flu shot prevented it”. […]