It is not always the driver who is responsible for car accidents, as a study has found that loud conversations and horseplay by passengers result in more serious accidents for teen drivers.
Teenage drivers were six times more likely to have a serious incident when there was loud conversation in the vehicle and three times more likely to have a serious incident when there was horseplay in the vehicle, said the study.
Young drivers were less likely to use cell phones and other technology when there were passengers in the car with them, the study showed.
But having multiple passengers in the car more often led to more serious incidents, the researchers found.
"This is why the limit of one teen passenger is important when teens are just learning to drive," said Robert Foss from University of North Carolina Highway Safety Research Center in the US.
For the study, young drivers were recorded in a variety of real-world driving situations over six months - with parents in the car, with other teens in the car and alone.
The study appeared in the Journal of Adolescent Health.