Hello Brandoshua.
There is a range of injuries in which you can gain from getting injured or by adding. These can be added by Civilians Only. This is across the Range for the Division with different parts of the Division being able to treat injuries.
If people wait for a certain amount of time whilst down they do die or are harder to treat, bring back and sometimes the Medical System also transfers them to the hospital.
We are eager for feedback on this and if you have any injuries in which you would like to be added please do let us know, Where we will review and pass the suggestions across to the development team.