Thus , the cumulative incidence of injury was 5.0 % ( 25 of 481 ) .
The average age at time of injury was 17.6 years , with a range from 11.9 to 20.9 years .
The cumulative incidence of injury was 5.0 % ( 25 of 481 ) .
The average age at time of injury was 17.6 years , with a range from 11.9 to 20.9 years .