"in the chart for preventable causes of death it has firearm. Not sure what the prevention is? bulletproof vest? Should it be suicide instead?" Prevention would include staying in safe neighborhoods (like you said), trying to not put others into murderous rages, and practicing proper safety techniques when handling guns.

"Nit: I am not sure how reference 21 for firearms relates." It doesn't; it must have been a typo. Edited.