The questionnaire contained 99 questions on distracted and sleepy driving. Since the focus for this report is sleepy driving, only 22 of the 99 total questions were extracted and analyzed for this investigation. These questions can be reviewed in the Appen- dix. Accident history questions included the number of accidents in the past 3 years, whether any of these accidents were related to being sleepy, and the number of near-miss accidents due to driving sleepy in the past 3 years. Other variables included de- mographics listed above and questions on professional driving, miles driven yearly, time of day driving, seatbelt use, alcoholic drinks per week, insomnia, sleep apnea, narcolepsy, motor vehicle accidents, sleepy near-miss accidents, and hours of sleep when working or not working. The questionnaire asked about current habits with respect to average alcohol consumption, sleep distur- bances, driving habits, and other variables. With the exception of miles driven per year and accident history (previous 3 years), we did not give a specific time frame but, rather, asked about current behaviors/status. Question 8 was from the Epworth Sleepiness Scale (ESS)19,20 and had a total of 8 answers. Our questionnaire was not previously validated, except for the ESS portion, which
has been validated for the propensity of sleep in 8 situations. The questionnaire posed simple, unambiguous questions on sleepi- ness, measures of sleepy driving, sleepy near-miss accidents, and accidents associated with sleepiness. It was designed, compiled, and reviewed by a group of university sleep researchers at the Stanford Sleep Disorders and Research Center at Stanford Uni- versity School of Medicine (Stanford) and the Division of Biosta- tistics at Washington University School of Medicine (St Louis), and the Sleep Disorders Center and Sleep Apnea Research Group at the University of Washington (Seattle).