4

None of the statistics I've seen on airbags' impact on safety/crash survival make any mention of seat belt usage. I think it's obvious that airbags make a big difference overall, but given the likely prevalence of seat belt misuse or non-use, it's not clear whether they provide significant benefit in the case where the driver/passenger is properly buckled in.

How strong is the evidence for their use in this case?

Sklivvz
  • 78,578
  • 29
  • 321
  • 428
R.. GitHub STOP HELPING ICE
  • 149
  • 2
  • 9
  • Please provide a citation for notability to your claim, otherwise this will be closed as opinion based. – Larian LeQuella Oct 21 '14 at 18:28
  • 1
    @LarianLeQuella Is the OP making a claim? They seem to be asking, "what's the evidence that airbags are effective, after removing the confounding effect of seatbelts?" That "airbags are effective" is a claim, but it's one I'd be inclined to accept as notable without a citation. – ChrisW Oct 21 '14 at 19:18
  • The title has received a good edit. Now, inside the question itself, please cite something that would substantiate your claim. In the meantime, this is an easy assertion to debunk. – Larian LeQuella Oct 22 '14 at 06:33

1 Answers1

8

I am not sure where you are hearing or looking for statistics to assert that airbags don't help if someone is buckled in. My very first google result was from the National Institute of Health, in 1992 already had good statistics:

Driver deaths in frontal crashes were 28 percent lower in cars equipped with air bags than in cars equipped with manual lap-shoulder belts only (Citation: Zador PL, Ciccone MA. Driver fatalities in frontal impacts: comparisons between cars with air bags and manual belts. Arlington, Va.: Insurance Institute for Highway Safety, 1991)

The National Highway Traffic Safety Administration goes on to say this particular item (emphasis mine):

Concerning overall injury reduction, for serious injury, the air bag plus lap-shoulder belt (when used) and manual lap-shoulder belts alone both provided about 60 percent reduction in injury risk, while automatic belts exhibited 37 percent effectiveness when they were used. The estimated effectiveness of the air bag alone was 7 percent (not statistically significant).

This is all well and good, however, the main benefit of airbags is the brain injury prevention. This paper at PubMed specifically relates:

Air bags prevent the violent whiplash motion of the head in a frontal crash, resulting in a more controlled deceleration of the brain. Wrenching forces exerted on the cervical spine are attenuated, and the face is protected from contact with hard or lacerating surfaces. Furthermore, compliance is not a problem with air bags.

Most of the statistics I have found are prior to 1995, which is before the introduction of side and various other airbags (versus just front airbags). A critique that has been leveled at airbags in the past is that they were really only effective in front impacts (which was true prior to the introduction of the various other airbags). Monash University concludes that padding on all surfaces (such as provided by airbags) goes a great way towards reducing brain injury (although they also recommend drivers wear helmets if they really want to be safe).

Estimated harm benefits are also given for other protective measures such as air bags alone, both front and side-mounted bags, and improved seat belt systems and penetration resistant side window glazing. The benefits are presented in terms of the savings per vehicle for two discount rates, 5 and 7 per cent.

Larian LeQuella
  • 44,977
  • 18
  • 187
  • 208
  • Re: your first sentence, I didn't hear such a claim. The title of my question was changed by an edit. Rather, I've heard various reports of serious injuries, some which escalated the nature of the crash, due to deployment of airbags, especially first-generation ones in older vehicles, and so I was looking for reliable information on which to weigh the risks and benefits. If that's not on-topic for this SE site, sorry. – R.. GitHub STOP HELPING ICE Oct 22 '14 at 16:13
  • 2
    I think this answer needs considerable work, since none of the cited sources actually addresses the question. The study in the first source merely shows (and this is explicitly stated as the conclusion) that drivers of cars with airbags have a reduced injury rate. It doesn't say why (i.e. they might be more likely to use their seat belts). The second study explicitly states in its abstract that the main benefit of airbags is that they are "always in use", and thus protect unbelted drivers. The third study also doesn't explicitly address the question, though it at least mentions the issue in. – John Doucette Oct 22 '14 at 21:27