WASHINGTON, D.C. — New research on the use of cell phones while driving revealed that hands-free devices provide little safety benefit. In a study conducted by the Virginia Tech Transportation Institute and the National Highway Traffic Safety Administration, 100 drivers were watched for a year, according to the Detroit News. The conclusion: The use of electronic devices, such as cell phones, led to many crashes and near-misses. There were nearly 700 incidents involving wireless devices, the study found. NHTSA researchers said that devices like head sets or voice-activated dialing — which had been suggested as potential solutions to driver distraction — led to longer dialing times than for those using hand-held phones. The delays offset the potential benefit of keeping both hands on the wheel. During the study, The NHTSA/Virginia Tech team used cameras and internal car sensors to track the activities inside a vehicle immediately before a dangerous event, including crashes, near-crashes, and “incidents” that required an evasive maneuver to avoid a crash. The 100-car study showed such events and accidents were often preceded by distraction, and the most frequent distrac-tion was the use of a cell phone or other electronic device. The next most-frequent source of distraction was a passenger, which preceded a problem situation nearly 400 times. Eating — another common distraction — led to risky behavior just over 100 times. NHTSA officials have expressed concern that hands-free devices can give drivers a false sense of security because research has shown that it is the act of conversation that leads to distraction and inattentive driver behavior. Auto companies and other researchers have also conducted research on how well hands-free de-vices help drivers stay focused. “The preponderance of evidence suggests that long conversations while driving impair your ability to react to events,” said Jeff Greenberg, director of Ford Motor Co.’s driving simulator. “But it would be difficult to make rules about conversations in vehicles.” In 2003, University of Utah professor David Strayer found that cell phone conversations led to a kind of “inattention blindness,” as drivers fail to recognize objects or events in their field of view. Strayer found that drivers using hand-held and hands-free cell phones were equally impaired. States, such as New York and New Jersey, and the District of Columbia, have banned drivers from using hand-held phones due to the potential dangers of talking on the phone and driving.