BLACKSBURG, Va. — Texting while driving increases the risk of a crash much more than previous studies have concluded, with motorists taking their eyes off the road longer than they do when talking or listening on their cell phones, a safety research institute said yesterday.

The Virginia Tech Transportation Institute used cameras to continuously observe light vehicle drivers and truckers for more than 6 million miles. It found that when drivers of heavy trucks texted, their collision risk was 23 times greater than when not texting.

Recent research using driving simulators suggested that talking and listening were as dangerous as texting, but the "naturalistic driving studies clearly indicate that this is not the case," a news release from the institute said. The risks of texting generally applied to all drivers, not just truckers, the researchers said. Complete results were expected to be released today.

Right before a crash or near collision, drivers spent nearly five seconds looking at their devices, which was enough time at 55 mph to cover more than the length of a football field.

"Talking/listening to a cell phone allowed drivers to maintain eyes on the road and were not associated with an increased safety risk to nearly the same degree," the institute said. "These results show conclusively that a real key to significantly improving safety is keeping your eyes on the road."

The institute recommended that texting be banned for all drivers and all cell phone use be prohibited for newly licensed teen drivers. Fourteen states, including Hawai'i, already ban texting while driving.