For many people, Memorial Day marks the beginning of the summer holiday season. But for the highway safety community, it is the beginning of a prominent high visibility enforcement campaign called Click-It-Or-Ticket.
As a native North Carolinian, this campaign has a special place in my childhood as well as in my professional career. Click-It-Or-Ticket was born in North Carolina in 1993. The hallmarks of a high visibility enforcement campaign are a media blitz followed by issuing lots of citations for violations. As a kid, I remember how the Ad Council promoted seat belt use through Vince and Larry, the crash test dummies. Today, the National Highway Traffic Safety Administration (NHTSA) has modernized their paid media spots to better relate to why people may choose to not use their seat belts.
After the period of education through TV ads, newspaper articles, electronic signs on highways, and other methods, the campaign continues with local and state law police beginning an enforcement period around Memorial Day weekend. That means conducting special patrols or checkpoints. Enforcement gets its own publicity through the local news or by affected citizens posting on social media that they interacted with a checkpoint or were issued a ticket.
The North Carolina Seat Belt Survey
As a statistician and project director, I studied seat belt use in North Carolina for several years on behalf of the North Carolina Governor’s Highway Safety Program (GHSP). Every state is required to conduct a statistically valid survey of seat belt use each year. While surveys are excellent for many data collection initiatives, we know that people tend to over-report behaviors that are deemed socially acceptable. Based on surveys alone, we would expect to find a high rate of people who floss their teeth, eat five servings of fruits and vegetables, walk 10,000 steps, and call their mother every day. That’s why the seat belt survey is an observational survey. The protocol for all states takes advantage of the period of publicity followed by enforcement, and times the surveys to happen in June when seat belt wearing rates may be the highest of the year.
This is where the surveys conducted by North Carolina differ from those of the rest of the country: trained interviewers are positioned at randomly selected controlled intersections. A controlled intersection is one with a stop sign or traffic light. Other states don’t require controlled intersections for the data collection, and that has an impact on the data quality as well as the safety of the field observer staff.
The Data Collection Experience
Put yourself in the role of a field observer. If a car, pickup truck, or SUV is at a traffic light, it seems like it would be easy to see if someone is wearing their seat belt. Unfortunately, that’s not true. You might battle the glare of sunlight on the windshield or windows in addition to the June heat. Seat belts can blend in with an occupant’s clothing or be obscured by long hair. And believe it or not, some cars don’t fully stop at stop signs!
Now consider a vehicle going past you while positioned on a sidewalk or roadway shoulder. Imagine what it is like to try to observe seat belt usage. Some may be passing at 35 miles per hour while others may be going at highway speeds. In some instances, a seat belt may be clearly present. A floral shirt and a black seat belt make for a good combination, and you can confidently record that driver is wearing their belt. But what about their passenger in the front seat? You also want to collect information on that person. What if you don’t clearly see the seat belt? Are you not seeing it because it is not buckled, because it is somehow blending in or obscured, or simply because the vehicle is moving too fast? How do you record that observation?
The quality of the data is dramatically reduced if observers are viewing vehicles moving at 55 mph to 75 mph.
Problems at Uncontrolled Intersections
When observers are positioned along the roadway and not at controlled intersections, two main problems are possible.
Observers may be tempted to “guess” if the seat belt is in use or not. Some states gather data about interstate or freeway traffic from bridges and overpasses. The quality of the data is dramatically reduced if observers are viewing vehicles moving at 55 mph to 75 mph. It may be possible to record some instances of positive seat belt use, but definitively capturing non-use will be difficult and may cause the observer to record their best guesses.
Observers may not be as physically safe from moving traffic. Field observers are required to work at the roadway to collect good data. In more urban areas, this may mean standing on a sidewalk and walking down a line of cars waiting at a traffic light. On interstates or in rural areas, this could mean walking along a roadway shoulder which is uneven and close to the travel lanes. Vehicles coming to a stop or going through a controlled intersection will be more likely to expect a pedestrian nearby and can reduce the potential for a crash or incident.
Why Survey Methods Matter
This difference in survey methodology makes it impossible to fairly compare the seat belt wearing rate between states. We’re not comparing states for issues of state pride. Seat belts save lives! There’s a strong inverse relationship between seat belt wearing rates and vehicle occupant serious injuries or fatalities. When seat belt wearing rates increase, these types of injuries decrease. North Carolina, along with most states have adopted the principles of Vision Zero. This means the state is using data-driven prevention approaches to eliminate roadway deaths and injuries. Click-It-Or-Ticket is one of those approaches. A state with an increasing seat belt use rate should also see a decrease in fatalities. If that relationship isn’t maintained, there may be other factors at play, including a flawed seat belt survey.
There are also some programmatic issues that need to be accounted for. The NHTSA regional offices commonly provide states a seat belt wearing target of 90 percent or higher. Not meeting a seat belt wearing rate target can trigger a comprehensive review of a state’s highway safety plan. This is an in-depth, week-long review process, which requires a lot of work on the part of the state and the review panel.
The various states’ surveys help us know what’s working in highway safety and occupant protection. States such as California, Oregon, Washington and Hawaii consistently produce seat belt rates in the mid- to upper 90s. Knowing whether these are accurate rates would help other states determine if they should glean programmatic and enforcement techniques from these examples to improve safety in their own states.
The first change needed is to mandate the use of controlled intersections for data collection. This will improve the quality of the data and help keep field observers safe while doing their jobs.
A New Direction for Seat Belt Surveys
Given the importance of high-quality seat belt data, I believe the regulations around state seat belt surveys should be updated. The first change needed is to mandate the use of controlled intersections for data collection. This will improve the quality of the data and help keep field observers safe while doing their jobs. The National Survey of Occupant Protection (NOPUS) has two parts to its survey, one of which requires controlled intersections. Making state surveys consistent with the national methodology would also help improve comparability between states and to the national survey.
Secondly, states should be required to contract with an independent research organization or university for design and data collection. Some states conduct their survey using Department of Transportation, highway safety office or police staff. This creates a conflict of interest since these staff have a motivation to prove a high seat belt use rate. Using an independent organization or university with a survey design and collection unit would be a good alternative. These contractors would be able to follow the protocols and provide data without it directly affecting their business.
Finally, if states use independent organizations, the state, local law enforcement and other highway safety office staff should not know the precise location of the surveyed intersections. The presence of police, whether purposeful or coincidental, near survey sites could artificially increase seat belt wearing rates and is not a true measure of seat belt rates in the state.
Craving more about seat belts? Bill Hall of UNC’s Highway Safety Research Center and I were interviewed by Brian Southwell on The Measure of Everyday Life podcast in 2015.