Temporal factors in motor vehicle crash deaths

To summarize fatal motor vehicle crash deaths in the United States by time of day, day of week, month, and season, and to determine why some days of the year tend to experience a relatively high number of deaths.

Crash deaths were identified and categorized using the Fatality Analysis Reporting System. Days of the year with relatively high crash deaths were compared to the two days that occurred exactly one week before and one week after.

On average, motor vehicle crashes in the United States result in more than 100 deaths per day, but there is much day-to-day variability. During 1986-2002 the single day fatality count ranged from a low of 45 to a high of 252. Summer and fall months experience more crash deaths than winter and spring, largely due to increased vehicle travel. July 4 (Independence Day) has more crash deaths on average than any other day of the year, with a relatively high number of deaths involving alcohol. January 1 (New Year's Day) has more pedestrian crash deaths on average, plus it has the fifth largest number of deaths per day overall, also due to alcohol impairment. On other days the high numbers of deaths are likely due to increases in holiday or recreational travel.

Every day of the year results in many crash deaths, but certain days stand out as particularly risky. The temporal and geographic spread of crash deaths, as well as the view of driving as a routine task, inures the public to this continuing problem. Innovative strategies are needed both to raise awareness and to work toward a solution.