This was sent to me by a listener, although I came across a reference a few days ago but didn't take time to read it at the time. Now I wish I had. Fascinating article. I've read numerous articles on stopping power (the idea of how a caliber performs at ending a threat) and this takes a different perspective but provides solid supporting evidence.
My main takeaway from it after reading the article is the following quote: "The results I got from the study lead me to believe that there really isn't that much difference between most defensive handgun rounds and calibers. None is a death ray, but most work adequately...even the lowly .22s. I've stopped worrying about trying to find the "ultimate" bullet. There isn't one. And I've stopped feeling the need to strap on my .45 every time I leave the house out of fear that my 9mm doesn't have enough "stopping power." Folks, carry what you want. Caliber really isn't all that important."