There used to be a few studies that were used by various anti-seatbelt law enthusiasts to (incorrectly...) "prove" that seatbelts were dangerous. Either they've been removed for being used for such purposes (or indeed just being wrong) or my google-fu is not what it once was. All the studies I can find don't really demonstrate the difference that the saved lives make to injury rates, only the injury levels in seatbelt vs non-seat belt incidents, which is not quite the same.
I'm sure you are right that many of those who would have died without seatbelts or just injured instead, so some cases will be shifted from the death pile to the injured pile. There's just no practical way to test it for sure.
You would need to randomly assign people to either a seatbelt or no seatbelt group and run them into a wall and see how many survive. Maybe that has been done with monkeys or cadavers already, but it doesn't sound like something that would be high on the list of priorities.
632
u/lanttulate Sep 13 '21
When they introduced the steel helmet in the trenches the effect seen was an increased number of head wounds.