Age of Causal Driver. This demonstrates the driver mix, which in this case might be skewed in the direction of the ages of school bus drivers. Causal Driver Race. Causal Driver Gender. Clearly, they are driving more than their share of buses.
Alcohol is a relatively low cause of school bus crashes.
Causal Vehicle Type. No inferences can be made of this variable since it reflects the subsets being compared. However, it does show the involved vehicle type mix. Clearly contributing defects are much more a factor with school buses than they are with most other vehicles. This analysis demonstrates the breakdown of the specific defects.