Effects of feedback on legally intoxicated drivers.

College-aged patrons leaving a drinking establishment were given feedback about their blood alcohol level (BAL): 24 were administered a Breathalyzer and were then read a statement on the consequences of driving with their BAL; 21 were shown a large chart and had to determine their own BAL from their weight and number of drinks consumed; and 21 were given no feedback. The two feedback groups were later collapsed. The subjects were also followed unobtrusively to determine whether they drove away from the premises. A total of 24 of the feedback subjects (47%) were legally intoxicated, but 83% of this group nonetheless drove after learning that they were legally intoxicated. In addition, when self-reports of consumption were compared with Breathalyzer BALs, a correlation of .82 was obtained.