Why a 5-Star Safety Rating Doesn’t Mean Your Car is Safe
Lab tests are no substitute for real-life data.
No reasonable person would look at a Smart Car ForTwo and a Chevy Tahoe and conclude that they are equally safe in a crash. Yet both vehicles receive a 4-star safety rating from the National Highway Traffic Safety Administration or NHTSA.
How does this happen? In short, the star safety rating system does not use real-life data on who survives in a crash. Instead, it uses a less helpful data source: a small number of laboratory tests.
The human cost of that oversight got real for me when my brother was in a head-on collision. Luckily, he was driving his 2011 Jeep Grand Cherokee and not his 2008 Audi A4 — both are 4-star rated. According to that rating system, both cars seem to be equally safe — but that’s not the reality.
The current safety rating system is failing us
Don’t get me wrong. In the past 25 years, this rating system has helped to save thousands of lives. Between 1990 and 2018, the number of people killed annually in vehicle-related crashes dropped from roughly 40,000 to 37,000. The numbers look much better when expressed as deaths per 100 million miles driven — from 2.08 deaths per 100 million miles to 1.14, a 45% decrease.
But many other changes in the transportation system contributed to this reduction. These include stricter driving laws, improved medical emergency response, and better car safety features.
The star safety rating system and the Top Safety Pick ratings from the Insurance Institute for Highway Safety or IIHS, have fulfilled one important mission. They spurred manufacturers to improve the crashworthiness of their cars. People today walk away from crashes that once meant certain death.
But these traditional, laboratory-based systems have failed in their second mission: to give consumers real information. This graphic helps explain why:
In summary, these laboratory-based systems produce ratings based on limited data and unrealistic situations. NHTSA and IIHS recognize these limitations. They even warn manufacturers not to make global claims about the safety of their vehicles based on these ratings.
However, many customers don’t know that unless they’ve thoroughly studied the fine print on these rating sites. And these limitations can cost people their lives.
Tesla recently used its high performance in the star safety rating tests to claim that the Model 3 is the “safest car ever built.” But it’s not. The federal government knows that and is challenging Tesla legally. Meanwhile, the Model 3 is now the top-selling Tesla to date.
As an auto safety expert, I think that this sets a very dangerous precedent.
There is a better alternative
The good news is that real car safety information exists. For 40 years, our government has collected information on all the vehicle-related, fatal crashes that occur on our roads.
This database contains hundreds of pieces of information about each event. Things like:
· Where the crashes occurred
· Who was driving (e.g., sex, age, license status)
· What vehicles were involved
· What kinds of crashes they were (e.g. head-on, side collision)
Most importantly, the database keeps track of who walked away and who perished. In total, it has millions of pieces of information that researchers in government, industry, and academia use to develop and evaluate car safety programs.
But consumers have not had practical access to this information.
It’s time to change that. This information could be invaluable in showing car buyers the actual track record of a vehicle: which cars protected their drivers in the worst crashes, and which did not.
When my brother chose to drive his Jeep Grand Cherokee that fateful night and not his Audi, he was lucky. After we spoke, my brother sold his Audi.
They say experience is the best teacher. But no one should have to learn the truth about car safety ratings after a crash when real, life-saving information already exists. As one car buyer recently told me,
You can have an inkling that something might not be the safest, but that’s different than knowing it.
Norma Hubele, Ph.D. is a Statistician, Professor Emeritus of Arizona State University, founder of TheAutoProfessor.com and creator of the only car safety rating system based on real crash data. And it’s free. Special thanks to Kendra Allenby for her sharp insights and terrific drawings.
