Michigan traffic deaths and severe-injury crashes drop

July 31, 2003
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ANN ARBOR, Mich.,—Despite what seems like a preponderance of dangerous drivers on Michigan roadways these days, traffic-related deaths and serious injuries are down since 1997, say University of Michigan researchers.

Fatal and serious-injury crashes in the state declined 27 percent from 1997 to 2001 (the most recent year for which data were available at the time of the study), while the number of people killed or severely hurt in vehicle crashes dropped 29 percent during that time. The proportion of all crashes that result in a fatality or serious injury also has decreased over this five-year period—from 3 percent to 2.3 percent of all crashes.

“The overall reduction in the number and rates of fatal and serious-injury crashes is a positive indication of Michigan’s traffic safety efforts,” said researcher Lidia Kostyniuk of the U-M Transportation Research Institute. “Forecasts based on present trends indicate that the downward trend in the proportion of such crashes will continue if current traffic safety efforts are sustained.”

A new study by Kostyniuk and colleague Linda Miller found that the rates of fatal and serious-injury crashes per population, licensed drivers, registered vehicles and vehicle miles of travel each dropped nearly 30 percent from 1997 to 2001. Further, Michigan’s fatality rates are lower than the national average for each of these four measures.

Compared with other states, Michigan has the 15th lowest crash fatality rate per population and per licensed driver. Its mortality rate is also 17th lowest per vehicle miles of travel and 20th lowest per registered vehicle.

Although drivers of all age groups have lowered their numbers and rates of involvement in fatal and serious-injury crashes since 1997, younger drivers are still much more likely to be killed or severely injured on Michigan’s roads, the researchers say.

According to Kostyniuk and Miller, the rate of fatal and serious-injury crashes per 1,000 licensed drivers is 4.38 for drivers under 18 and 3.6 for drivers 18-24. For young male drivers, the rates are even worse—5.07 for those under 18 and 4.49 for men 18-24. In contrast, the rate for all drivers over 70 is 1.12.

While speeding, tailgating and failing to yield are the most commonly reported hazardous driver actions in fatal and severe-injury crashes, drinking and driving and not using seat belts are also problematic, especially among drivers 18-24, the researchers say.

They found that alcohol-related crashes remained at about 12 percent of all fatal and serious-injury crashes between 1997 and 2001, despite a 30 percent decrease in the overall number of drinking and driving crashes resulting in death or severe injury.

“The decrease, however, was not uniform across all age groups,” Kostyniuk said. “The smallest decreases in numbers and rates of fatal and serious-injury crash-involved drivers who had been drinking were among drivers 18-24. This age group consistently had the highest rate of involvement in ‘had been drinking’ crashes per licensed driver over the five-year period.”

In fact, the proportion of drivers 18-24 involved in a fatal or serious-injury crash and who had been drinking has increased from 23 percent to 28 percent, the results show. Again, the rate was especially high among male drivers in this age group· -about 35 percent higher for these younger men than for male motorists 25-34.

Another high-risk behavior common among younger drivers is the failure to wear seat belts, the researchers say. In 2001, 68 percent of drivers under 24 who were involved in fatal or serious-injury crashes wore a seat belt, compared with 74 percent of such drivers 25 and older. Further, drivers under 18 involved in fatal or severe-injury crashes, specifically, are the only group to show a decline in seat belt usage since 1997 (decreasing from 69 percent to 65 percent).

Even among passengers involved in fatal and serious-injury vehicle crashes, whose safety belt use was lower than drivers across the board, the rate is lowest (48 percent) among passengers 18-24 than for any other group. Overall, seat belt use is 15 percent lower for passengers than for drivers in all groups.

Other findings from the U-M study, which was sponsored by the Michigan Office of Highway Safety Planning, include: · Speeding is the most frequent hazardous driver action in single-vehicle fatal and serious-injury crashes. · Failing to yield, following too closely and violating traffic controls are the most common hazardous driver actions in multiple-vehicle fatal and serious-injury crashes. · One-third of drivers involved in fatal crashes, who were tested for blood alcohol, tested positively and about 26 percent were legally drunk (with a blood alcohol level of at least 0.10). · Of tested drivers who had even a drop of alcohol in their system, 84 percent exceeded 0.8, the new legal limit effective this fall. · The proportion of women among drivers involved in fatal crashes who tested positively for alcohol increased from 13 percent in 1997 to 18 percent in 2001. · The number of children under 5 who were killed or severely injured as passengers in vehicle crashes has dropped 19 percent since 1997; for those children 5-15, the decline is 25 percent. · The number of fatal and serious-injury crashes involving motorcycles is up 11 percent from 1997-2001, but down 28 percent for large trucks, 26 percent for bicycles and 19 percent for pedestrians.