The four E's of crash analytics: Part 1


The leading cause of death for Americans between 5 and 34 isn’t what most would expect.  It’s not disease or acute illness. It’s traffic crashes. The good news is that the number of highway deaths has steadily decreased the last few years, yet crashes still cause more than 30,000 fatalities and send two million people to the emergency room each year.

Not only are the deaths and injuries resulting from these crashes devastating to those involved, the societal and economic costs can be expensive. AAA estimates that crashes cost society $299.5 billion annually and believes that an investment in data collection and analytics is imperative to ensure that resources are spent in a way that yields the greatest possible results. A study conducted by the University of Michigan Transportation Research Institute shows that in Michigan alone the total societal costs associated with motor vehicle crashes reached $9.1 billion in 2009—outpacing societal costs for all other types of crime combined.

In an effort to combat these high costs, deaths and injuries, state departments of transportation (DOT) work closely with law enforcement agencies, state traffic safety offices and the National Highway Traffic Safety Administration (NHTSA) to plan and implement policies that can help reduce the number of motor vehicle crashes. One approach is through the Four E’s of traffic safety—Enforcement, Engineering, Education and Emergency Medical Services.

Over the past few years, the Four E’s approach has contributed to a steady decline in both fatality and injury rates. While this decline in traffic crashes and the resulting deaths and injuries is good news, NHTSA, law enforcement, state DOTs and state highway safety offices are not resting on their laurels—they continue to work toward keeping the roads as safe as possible.

The ultimate goal these groups are striving toward is ambitious, but they believe achievable. Toward Zero Deaths (TZD) is a data-driven highway safety strategy that focuses on changing the driving culture, with the goal of no deaths on the nation’s highways. Statistically, that means to get the fatality rate per vehicle miles traveled (VMT) to zero. Today, the rate is 1.14 fatalities per 1 million VMT. The TZD initiative relies on data from crashes and police stops, in concert with the four E’s, to determine priority areas and make changes to policies and programs.

The Four E’s play an important part in road safety. Each component is essential and when taken together as a unified approach, has had great success helping to achieve the lowest crash rate in decades. By addressing the four components in a holistic way, NHTSA, state DOTs, law enforcement and state traffic safety offices hope that they can prevent crashes from happening in the first place. Those groups are exploring how technology can improve and transform the way traffic safety advocates, traffic safety engineers and other key stakeholders use the Four E’s.

Data from the Four E’s can include:

  • Vehicle speed
  • Traffic volume at the time of the crash,
  • Law enforcement crash investigation information
  • Emergency medical response information
  • Road sensor and design data
  • Effectiveness of public education campaigns

This can be analyzed holistically to help decision makers create strategies for comprehensive traffic safety improvement plans. Unfortunately, the data often resides in different agencies, in various databases, formats, and types of hardware. Integrating the data and creating a holistic view of traffic safety would allow for a coordinated approach to preventing crashes. Furthermore, analytics gives road designers, law enforcement officers, emergency medical responders and those designing public education campaigns the ability to identify trends and develop highways safety plans and interventions that will have the best return on investment in terms of reducing the crash rate.

I will dive deeper into each of the four E's in future posts. Stay tuned!


About Author

Melissa Savage

Sr Industry Consultant, State and Local Government

Melissa Savage is a subject matter expert with SAS Institute, Inc. focusing on transportation issues facing state and local governments. Prior to her position with SAS Institute, Inc. Ms. Savage was a Program Director at the National Conference of State Legislatures (NCSL) in the Energy, Environment & Transportation program. During her 13 years with NCSL, Ms. Savage authored several publications on transportation issues, testified before state legislative committees and represented NCSL and the interests of state legislatures before national transportation organizations and working groups on a variety of topics. Before working at NCSL, Melissa worked in the Office of Legislative Legal Services at the Colorado General Assembly. She received her master’s degree in public administration from the University of Colorado and her bachelor’s degree from Colorado State University.


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