The study analyzed nearly 30 years of data from 1980 to 2009 and found an average of 13 more traffic deaths that happened on Tax Day compared to other days in April. That might not sound like a lot, but Dr. Donald Redelmeier said it means an average of about 13 extra deaths per day and amounts to about $40 million in annual losses to society.
Redelmeier, who is a physician and researcher at the University of Toronto, said that estimate includes loss of life, injury and property damage costs.
Electronic tax filing started in 1986 and became increasingly popular during the study period, but it appeared to have no effect on Tax Day deaths, Redelmeier said. He added that filing electronically can be stressful as well, and it might even encourage people to wait until the last minute to do their returns. For those reasons, he said it's unlikely that universal e-filing will result in fewer Tax Day deaths.
According to the study, stress and reckless driving may be reasons for the increase as people try to beat the tax deadline. Drivers were slightly less likely than passengers and pedestrians to be killed.
Previous research found the Fourth of July as the deadliest day for traffic fatalities. A spokeswoman for the Internal Revenue Service declined to comment on the study.
Typically, Tax Day falls on April 15, but this year, the IRS postponed the deadline by two days to April 17. That's because April 15 is a Sunday and the next day is Emancipation Day - a public holiday observed in Washington, D.C.
The study utilized data from the National Highway Traffic Safety Administration. The results appear in Wednesday's Journal of the American Medical Association.
The Associated Press contributed to this report.