Drinking and driving: a comparison of deceased drivers and roadblock control motorists.

68% of the drivers who died within six hours after highway crashes had alcohol in their blood and 44% were legally impaired; that is, had 100 mg% or higher. In the roadblock sample, however, alcohol was present in 13% of drivers who were stopped under similar conditions of time and place to the crashes, and only 3% had 100 mg% or higher.