Make no mistake, using your mobile phone without a handset is both dangerous and stupid. It's illegal for a reason.
But given all the hype surrounding phone use in cars, one would think that this was the most dangerous form of distracted driving.
However, a new study just undertaken in the USA by Erie Insurance shows otherwise.
The research was compiled using police data and it showed that in 62 percent of the cases where distraction led to a fatal crash, the at least one of the drivers was "lost in thought" or "generally distracted".
The second biggest cause of distraction was cell phone use, at 12 percent, followed by outside people/objects/events (at seven percent) and other occupants (five percent).
A number of other distractions - such as eating, drinking and operating the radio or climate controls - each accounted for another two percent, while smoking was to blame in one percent of instances.
"Distracted driving is any activity that takes your eyes off the road, your hands off the wheel, or your mind off your primary task of driving safely," said Doug Smith of Erie Insurance.
"We looked at what law enforcement officers across the country reported when they filled out reports on fatal crashes and the results were disturbing. We hope the data will encourage people to avoid these high-risk behaviours that needlessly increase their risk of being involved in a fatal crash."
But the bottom line is that being mentally distracted is still one of the most dangerous things you can do behind the wheel. We all do it and it's almost unavoidable, given how driving has become such an 'automatic' process.
Training ourselves to concentrate on the task at hand is the only real solution.