Study was very subjective Brooke. Even Evan admits his data is to be used as a guide only. First off the data pool is small. Second its a statistical fact that at least 5 out of 6 people shot with handguns will survive, and a BG still breathing is a BG who is dangerous.
The author himself admits he doesnt, and couldnt, use the types of bullet as a factor in the study. Now since the type of projectile is as important as the caliber itself the lack of inclusion of said data, ITSELF, invalidates the study. My guess is he uses a lot of military data cause 1/2 of his 9mm info is from ball ammo and ball ammo is just not an effective bullet design nor does it transfer energy as effectively as JHPs or even Lead.
His use of head shots is also an aberration that I dont believe Evan used. The reason why is because head shots are notoriously unreliable. Not only is the CSN a small target but there are even parts of the brain that, even when hit, wont stop the attack. There are only three small target area's in front, side, and base, of the head that CAN cause a immediate shut down when shot with a handgun. Ive seen guys hit in the head with a .45 have the bullet wrap around their skull and they themselves walk to the hospital. One guy drove after getting hit accidentally on NY Eve.
To his credit the author admits at the end that most of his data really doesnt mean much. This has always been the problem with such studies, that the fact that there are just to many "unknowns" in these incidents that how very hard to quantify. The author does make one statement that I dont agree with and thats regarding the use of mouse guns. He leaves the reader feeling a .22 is just as good as a .38 and that just isnt so.
When I first started this business over 30 years ago "most" of what we took from these gangsters, and most of what they used, was all .22s, .25s, .380s, and almost always ball ammo. The guns themselves were pretty much crap like Lorcin's or Astra's. Now I cant even remember the last gang shooting I handled where a cheap mouse gun with lousy ammo was used. They have grown more sophisticated and rich with drug money "I suspect the Internet" and nowdays a quality 9mm and quality JHPs are a minimum for the gang "shoota's". I was even once shot at by a shooter who had a .357 and 125 JHPs.
Now one would think there would be a corresponding increase with stops and fatalities with the use of better weapons and bullets ; However, There has also been a corresponding advancement in emergency medical science and EMS response times. Wounds that were almost always fatal 30 years ago are now routinely survivable. But all in all theres no way I'd ever tell anyone to carry a .22 to protect themselves.
I once had a .22 Beretta and had it in my pocket when two guys tried to rob me one morning. Without going into detail the piece did not bring me comfort and I sold it the next day and never again carried a mouse gun.