New Delhi, July 4 -- A new study has raised serious concerns about distracted driving among teenagers, revealing that teen drivers in the United States spend as much as 21% of their time behind the wheel looking at their phones.

The research, conducted at Brigham and Women's Hospital in Boston, involved survey responses from 1,126 teen drivers across all four regions of the U.S., along with in-depth interviews with a smaller group of high schoolers. The findings paint a worrying picture of how frequently smartphones are used while driving, even when young drivers are aware of the risks.

What's particularly alarming is that more than 5% of the total driving time involved glances at phones lasting two seconds or longer, enough to qualify ...