bad statistics – car seat safety

car helmet while drivingNews reporters are notoriously bad at basic comprehension of statistics. When it comes to child safety in cars, there is no exception.

From CBSnews:

For children, the back remains the safest place to ride. Children 12 and younger account for 56 percent of passengers who sit in the back of vehicles, but only 24 percent of crash fatalities, according to a recent study by the IIHS and the Children’s Hospital of Philadelphia that reviewed U.S. accidents between 2007 and 2012.

CBS news claims that “For children, the back remains the safest place to ride.” The best way to show this would be some sort of comparison between children killed or injured in the back seat versus the front seat. Even that might be further controlled for driving habits of the parents (maybe more reckless parents allow their children to ride in the front more), age of the child (maybe parents who let their children ride in front do so long after they are out of 5 point harnesses) and safety measures taken for the child (maybe parents who let their children ride in front also tend to be less rigid on safety belts).

But the news article does not claim any such comparison. Instead, the story compares back seat children to back seat adults! This methodology actually provides zero information about the relative safety to children between the various seats. What this does tell the audience is that children sitting in the backseat are less likely to be injured than adults sitting in the backseat. The same might very well be true about front seats. It could easily be the case that children sitting in the front seat are safer than adults sitting in the front seat. We don’t know, but if the reasons that children are safer in the back seat hold true for the front, it is a probable assumption to make.

By the statistics that this article presents, the only possible implication for the adult reader is to grow younger if they want to be safer in the back seat. This is something that is impossible; it is useless information. The article would have been better without these factoids.

In any case, there are plenty of good reasons that might account for the discrepancy in injuries between adults and youth. Youth tend to have 5 point harnesses. People often drive slower and less recklessly if they are driving around their own children. Parents with children often do not drive on long trips in unfamiliar territory. People with children tend to drive bigger vehicles. People with a lot of children tend to live in more rural areas. The list goes on. All else being equal, the natural assumption should be that in the same accident that children are more likely to be hurt due to their more fragile bodies. The fact that the statistics do not represent this tells the reader that children and adults do not have the same car accidents. Again, all useless information to adults. The implication would be “take less trips and drive more carefully” (in other words, common sense).

But the article shows no familiarity with how statistics work or how they are interpreted. Instead it takes a vague claim (how much more unsafe is the front from the back seat?) and supports that claim with totally irrelevant statistics. The result is fear mongering towards parents who let their children ride in the front seats (something perfectly legal in many states). Perhaps one day a reporter might be able to quantify exactly how much more likely a child is to get injured over the long run sitting in the front seat rather than the back. I won’t hold my breath.

About christopher fisher

The blog is meant for educational/entertainment purposes. All material can be used and reproduced in any length for any purpose as long as I am cited as the source.
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