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 Monday.

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.

Dialing a cell phone and using or reaching for an electronic device increased risk of collision about six times in cars and trucks.

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 statement from the institute said. The risks of texting generally applied to all drivers, not just truckers, the researchers said.

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.

The study also concluded that headset cell phone use is not substantially safer than hand-held because the primary risks associated with both are answering, dialing, and other tasks that take drivers’ eyes off the road.