Teenage drivers who start school classes earlier in the morning are involved in significantly more motor vehicle accidents than their peers who have a delayed high school start time, says a new research.
"There are more and more data suggesting that insufficient sleep is common in our teenagers and that early high school start times are a contributor to teenagers' reduced sleep," said Robert Vorona, principal investigator, lead author and associate professor at the Eastern Virginia Medical School in the US.
"Insufficient sleep appears to have deleterious consequences such as decrements in mood, increased risk taking, impaired academics and increased crash rates," Vorona added.
The study showed that the weekday crash rate for teenage drivers during the 2009-10 school year was about 29 percent higher in Chesterfield county, where high school classes began at 7.20 a.m., than in the adjacent Henrico county, where classes started at 8.45 a.m.
Similar results were found for the 2010-11 school year, when the weekday crash rate for teenagers in Chesterfield county was about 27 percent higher than for those in Henrico county.
In contrast, there was no difference in adult crash rates in the two counties for either year.
A secondary analysis evaluating the causes and types of crashes found that Chesterfield County adolescents had a significantly higher incidence of run-off-road crashes, which is a common feature of drowsy driving accidents.
The findings appeared in the Journal of Clinical Sleep Medicine.