Young unlicensed drivers and fatal road traffic crashes in the USA in the past decade. A neglected public health issue.

It is unknown whether road traffic crashes (RTCs) involving young unlicensed drivers follow the downward trend of those involving licensed drivers. Our national register-based study from 2000 to 2011 indicates that the downward trend for young unlicensed drivers (<25 years) is significantly less pronounced. These drivers account for 10.7% to 11.5% of the fatal RTCs involving young drivers during that time period; this percentage is consistently higher in the Western and Southern states and has increased in recent years in the Midwest.