THE VALIDITY OF POLICE ASSESSMENT OF DRIVER INTOXICATION IN MOTOR-VEHICLE CRASHES LEADING TO HOSPITALIZATION

We evaluated the accuracy of the field sobriety assessment of police o fficers following a motor vehicle crash. Using linked data from a stat ewide traffic crash database and the trauma center registry, the resul ts of a field sobriety evaluation for each driver were compared with a blood alcohol concentration (BAG) drawn in the emergency department. BAC values served as the ''gold standard'' in which drivers with value s over 0.1mg/dl were classified as intoxicated. The subjects were driv ers over age 15 years who were admitted or died at Level I trauma cent er as a results of motor vehicle crash injuries during 1986-1993. A to tal of 1336 subjects had both a recorded BAC and a police sobriety ass essment. Seventy percent of subjects were male and 79% under the age o f 35 years. Overall, 40% of all subjects were judged by police to have been impaired, based on the scene sobriety assessment. Among all driv ers, the field assessment had a sensitivity of 91%, a specificity of 9 0% and a predictive value positive of 85%. After excluding the 419 dri vers which had breath testing as part of their assessment, the field a ssessment had a sensitivity of 74% and a specificity of 97%. The sensi tivity of the field assessment did not vary appreciably by gender but was lower among older drivers, and higher among severely injured drive rs and those involved in weekend and nighttime crashes. Police officer s in this sample appear to recognize drunk driving with a high degree of accuracy when investigating crashes in which the driver is transpor ted to a trauma center. Copyright (C) 1996 Elsevier Science Ltd.