Men are more likely to die in car crashes, as they typically drive more miles and engage in risky behaviors like speeding and driving impaired. However, estimates show that when comparing men and women involved in crashes of similar severity, women have a greater risk of sustaining serious injuries or being killed.

To examine the inequalities of car design and the resulting injuries, researchers of a recent study used trauma injury data from car crash victims and evaluated the differences in injury patterns sustained by men and women involved in car accidents.

"We found that vehicle crash injury patterns and injury severity differ between men and women. We also show that women are arriving at the trauma bay with signs of shock more often than men, regardless of injury severity. These novel findings of sex differences in shock index mean we need to look further into how and why this is happening," Dr. Susan Cronn, the first author of the study from the Medical College of Wisconsin, said in a news release. The findings were published in the journal Frontiers in Public Health.

The study also investigated if occupant crash systems work equally well for male and female bodies. For this, researchers used clinical injury data from more than 56,000 car crash victims. Half of the cases were women.

They noticed that even though men sustained more overall injuries, women had more pelvis and liver injuries. They also found that female victims surpassed a shock index greater than 1.0 more frequently than men, even in cases when they had fewer total or less severe injuries compared to men.

"An elevated shock index can be an early warning sign of hemorrhagic shock, caused by heavy blood loss, but can also be an early predictor of mortality," the news release stated.

"Our findings might mean that women's bodies have less capacity to function when physiological changes occur, that some injuries have more impact on female bodies, or that female bodies handle blood loss differently than male bodies. It might also be that we have been assuming that normal vital signs are the same for everyone regardless of sex and that we need to revisit our definition of normal," Cronn said.

The study did not include the diastolic blood pressure data of the victims, which could have made shock index calculations more precise. Another limitation is that the study did not take into account the vehicle size, type of crash, and other factors of crash dynamics, which could have affected the sex differences in crashes.

However, the findings highlight the need for changes in how first aid responders and medical professionals treat patients involved in car accidents based on sex-specific shock index. The researchers hope their study results will influence the design of the car safety development.

"We hope that we can delineate the impact of sex on crash injury further, so that vehicle safety engineering can consider important male and female body differences in their design, and that they provide insight for legislation and regulations as needed for equity in car safety design," Cronn said.