How to measure driving ability under the influence of alcohol and drugs, and why

Car driving performance is easily disrupted as a consequence of the use of alcohol and/or (il)licit drugs. Various aspects of vehicle handling have been used to measure drug effects, including: lateral position deviation, steering wheel handling, speed control, use of pedals and headway control. Alcohol, as well as producing changes in physiological measures of heart rate, significantly affected measures of vehicle handling. Similar impairments have also been found during the day following nocturnal use of hypnotics. The direction of drug effects on car handling skills is facilitated by appropriate methodological strategies for the monitoring of driver impairment. (C) 1998 John Wiley & Sons, Ltd.