"This is a huge problem," Tsifrin said. "Because they're too young to drink legally ... they're also less likely to call their parents to come and get them. It's more likely for a 22-year-old to call their parents and tell them to pick them up."
Of course, alcohol isn't the only influence: A 2007 State Farm/CHOP survey found that 38 percent of teens reported seeing other teens drive high. A study in 1999 by NHTSA and Maastricht University in the Netherlands found that after low doses of marijuana, reaction times worsened by 0.9 seconds when moving at 59 mph in test conditions. That translates to an extra 78 feet of travel. With both alcohol and marijuana, reaction times were 1.6 seconds, or 139 feet, worse.
At 60 mph, a typical car needs between 120 and 140 feet to reach a full stop. Most SUVs require an extra 5 to 10 feet on top of that. Consider that 60 mph translates to 88 feet per second, and it's easy to see why maintaining a proper following distance is a critical step in preventing accidents. Unfortunately, many teens fail to do so: In the NIH study, teen drivers left nearly two-tenths of a second less following distance behind the car ahead than did general traffic. Even at 40 mph, that's 10 feet less stopping distance.
Tsifrin blames it on driving tactics that flaunt swagger over safety. "They want to drive aggressively as far as showing off," he said. "There's still the kind of high school attitude of 'Who am I in the pecking order?'"
A 2006 survey by NHTSA reported that 76 percent of drivers age 16 to 24 said they wore their seat belts regularly, which NHTSA says is the lowest of any age group.
Tsifrin blames the lack of usage on many young drivers' sense of invincibility — "the hubris of youth," he called it — which also factors into teen speeding. Fortunately, many cars today have seat belt reminders that flash warning lights or chime until belts are secured. Call them annoying, but they help keep occupants buckled.
Not Being Able to Handle Emergencies
Knowing how to avoid an accident comes with driving experience. Young drivers can only learn so much in the classroom, which leaves learning maneuvers like straightening out a skid or how to apply the brakes correctly to real-world experience. Speeding and distracted driving only make things worse, Tsifirn said, as they compound the lack of experience by putting drivers at higher risk of encountering an emergency situation in the first place.
Drowsy driving affects an unlikely group — the so-called "good kids," Tsifrin said. That means straight-A students or those with a full plate of extracurricular activities.
"Overachievers have a lot of pressure here," he said. "If they're playing varsity sports and are also preparing for an AP English exam, and if they've been going from 7 a.m. and now it's midnight and they have to get home, they don't think, 'I'm too tired to drive.'"
Fatigue can affect more than just the valedictorians and star athletes. Three-fourths of teens in the State Farm/CHOP survey said they had observed their peers driving while fatigued. Across the general population, NHTSA estimates that fatigue and sleep deprivation contribute to some 100,000 reported crashes and 1,500 deaths each year.
Choosing the Wrong Car and Not Maintaining It
Too often, a combination of tight budgets and high style leads teens to pass up important safety features for larger engines and flashy accessories.
"A teen or novice driver ... will opt for a cool-looking sports car rather than a car that's really a safer choice," Tsifrin said. "Then, if they sink all their money into it, they might be remiss in maintaining it."
That doesn't just mean forgetting to check tire pressure or picking a car with a sunroof instead of one with antilock brakes. It can also translate into buying oversized SUV wheels that look fancy but reduce highway stability, or getting a performance stereo that drowns out potential hazards a driver might hear, such as an ambulance siren.