According to a university study a decade or two ago, airbags aren't as safe as we think. You are 26% more likely to survive a severe collision, sounds good right? You are 400% more likely to sustain severe injury or death from the airbags themselves in a moderate collision. Not so good...
While the second part can simply be measured from statistics, how do they measure the first? This 26% was based on government safety studies. Did they have high speed cameras in all of the severe collision vehicles and was a forensic doctor dispatched to each accident scene?
I read this years ago, so maybe I misquoted the percentages some or they have changed, but you get the picture.
Ever wondered why racing cars don't use airbags?