Are all drivers who drive at high risk? : the role of exposure in determining the risk of collision.

Differences in exposure is a variable which has been difficult to measure and frquently ignored in epidemiologic studies of traffic accidents. To study exposures 3000 drivers were interviewed by telephone. Drivers with more demerit points has driven significantly more than drivers with fewer demerit points. Drivers who drove small amounts each week has a much increased risk of collision per mile.