People who send text messages while driving are six times more likely to crash, a new study finds.

The research adds to a mountain of evidence showing that texting or talking on mobile phones while driving is dangerous. Texting seems to be the worst.

The new study was done in a driving simulator, however, so it's not known exactly how the results would translate to the road. Still, the results were stark.

In the simulations, drivers tended to decrease their minimum following distance when texting and also experienced delayed reaction times — meaning among other things they were slower to hit the brakes when needed. Drivers' median reaction time increased by 30 percent when they were texting and 9 percent when they talked on the phone, compared with when they were just driving.

Drivers who were texting also showed impairment in forward and lateral control than did drivers who talked on a cell phone while driving or drove without texting. A study earlier this year found that 60 percent of teens "drive while texting," or DWT.

Previous studies had found that adults who talk on cell phones while driving in simulators perform as dismally as drunken study participants.

When talking on a cell phone, "drivers apparently attempt to divide attention between a phone conversation and driving, adjusting the processing priority of the two activities depending on task demands," the researchers behind the new study write in the journal Human Factors. That split in attention is worse than conversing with someone who is in the car, past research has found.

Texting is a whole other matter. It "requires drivers to switch their attention from one task to the other," the researchers said in a statement today. "When such attention-switching occurs as drivers compose, read, or receive a text, their overall reaction times are substantially slower than when they're engaged in a phone conversation."

Reading text messages affected braking time more than did composing messages.

The research was done by University of Utah psychologists Frank Drews, Dave Strayer and their colleagues. The simulations involved 20 men and 20 women between the ages of 19 and 23. The participants were described as experienced texters who had been driving an average of 4.75 years.

In January, the National Safety Council called on state and federal lawmakers to ban the use of cell phones and text-messaging devices while driving and also urged businesses to prohibit it.

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