Women are 73% more likely than men to suffer serious injuries in a car crash. The comparison may sound shocking at first, but consider that crash-test dummies are models of the average male and things begin to make more sense.

Overall, car crash injuries are on the decline. Recent studies indicate that riders are much safer in newer models. Looking at the crash data on 31,000 people between 1998-2015, those riding in new models are half as likely to sustain serious injuries. But while fewer people in total are getting badly hurt in crashes, women are still comparatively much worse off, even when they wear their seatbelts.

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So far, no one knows exactly why females are so much more likely to suffer serious injuries in car crashes. Researchers have been searching for the answer for over a decade, but they still have not found it. However, the fact that crash test dummies represent an average's man's body stands out as a clear problem.

There are some obvious distinctions between male and female biomechanics. Jason Forman, a principal scientist at UVA’s Center for Applied Biomechanics and one of the authors of the study, points out that female pelvises are wider and shallower compared to males. Fat is also distributed differently between the sexes, with females having more concentrated around the hips and thighs, while males' fat is distributed more evenly or concentrated in the belly.

There are many other subtler differences between male and female anatomy that the researchers need to account for.

So why aren't crash-testers using female dummies? First of all, the male dummies have statistically been very successful in reducing total injuries overall. Nevertheless, women are still at a much higher risk. Secondly, some female crash dummies have been used, but they represent a very small woman, not the average women.

Clearly, a wider variety of body types still need to be tested and investigated.

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