Motor vehicle accidents, fatigue and optimism bias in taxi drivers.

Fatigue-related variables and their relationship with accident involvement were examined in a group of 42 Sydney metropolitan taxi drivers across a 2-year period. Advantages associated with the study of this group of road users include their important role in public transport, long hours spent on the road, job-related controls of exposure through shift patterns and the ability to verify accidents with company insurance records. Number and length of breaks, employment type, falling asleep at the wheel and a variety of other job-related and attitudinal variables were surveyed. Results provide basic data on fatigue-related aspects of the job of taxi driving. Driver time-on-the-road is often considerable: 67% of those surveyed drove at least 50 hours per week, yet time off in long shifts (up to 12 hours) was often short (as low as 3 minutes, with an average of 37 minutes). Self report of accidents proved reliable against insurance company records. A significant negative correlation between total average break time and accident rate was observed. Optimism bias was present for a variety of driving-related questions, including the ability to drive safely while fatigued.