Davis Law Group, P.S.

The Daylight Savings Time Switch and Increased Accidents

A study shows an increase in traffic accidents immediately following the spring daylight savings time shift.

When clocks are set back an hour in the spring, accidents go up according to a 1998 study of the effect of daylight savings time. Sleep deprivation is considered the most likely cause of a 17 percent increase in accidents on the Monday following the time change. The study also found no significant reduction in accidents in the fall when clocks are set back an hour.

The study used data from NHTSA's Fatal Accident Reporting System from 1986 to 1995. The same researcher had concluded in 1996 that sleep deprivation led to a 6.6 percent increase in non-vehicle deaths after the spring change, with an insignificant 1.5 percent decrease following the fall clock change.

Psychologist Stanley Coren, Ph.D., from the University of British Columbia reported his research in The New England Journal of Medicine showing a seven percent increase in traffic accidents the day after Daylight Savings Time and a seven percent decrease in accidents in the Fall when the clocks return to Standard Time. "We're all sleep deprived anyway so that extra loss you experience is enough to lead to an accident," says Dr. Coren. He is now studying the effects of sleep deprivation on the immune system.