In robberies and assaults, victims are far more likely to die when the perpetrator is armed with a gun than when he or she has another weapon or is unarmed.
Injury rates were higher for robbers with knives, but people are probably less likely to fight back or otherwise provoke a robber with a gun.
From http://www.ncjrs.gov/txtfiles/fireviol.txt
Injury rates were higher for robbers with knives, but people are probably less likely to fight back or otherwise provoke a robber with a gun.