Analyze This: A good reason to drive with an adult in the car | Science News for Students

Analyze This: A good reason to drive with an adult in the car

Teens with new driver’s licenses take more risks than do those who are just learning to drive
Oct 11, 2018 — 6:30 am EST
a teenage girl sitting in the front seat of the car with her hands on the wheel, looking into the backseat of the car

Teens are eager to drive alone once they get their driver’s license. But it is much safer to keep driving with an adult.


For many teens, getting a driver's license is an important milestone and a step toward independence. But having a license doesn’t ensure a teen will drive safely. Car accidents are the leading cause of teen deaths in the United States. And newly licensed teen drivers are twice as likely to have a fatal car crash per mile traveled as are teens who have been driving for a year or two. That’s according to the Centers for Disease Control and Prevention (CDC).

Here’s the good news. Teens who have learner permits and drive with an adult in the car seem to be fairly safe drivers. And even with a license, they tend to be safer drivers if there is an adult riding along. These findings come from a July study in the Journal of Adolescent Health.

In that new study, researchers outfitted 90 cars with sensors, cameras and GPS devices for at least 21 months. This allowed them to track and record drivers’ behaviors on the road. For the nine or so months that these teens had only a learner’s permit, they had to drive with a parent or adult guardian. During the year or so after the teens had gotten their licenses, they tended to drive solo. The researchers compared data from novice drivers or teens who had recently received a license to those from more experienced adult drivers.

Scientists refer to one type of on-the-road events as KRDs. That’s short for kinematic (Kin-eh-MAT-ik) risky driving. This class of erratic behaviors affect a car’s motions. These include how many times drivers braked suddenly, how often they accelerated quickly or how many times they turned sharply per 1,600 kilometers (1,000 miles) traveled.

Such erratic behaviors make it harder for the driver to quickly respond to a sudden change in traffic. That might be an abrupt slow-down due to an accident up ahead. Or it could include a truck that suddenly swerves because of a flat tire. These KRD events also make it hard for adjacent drivers to predict what a vehicle will do. Researchers hope that finding ways for teen drivers to reduce KRDs might cut their risk of auto accidents.

a graph showing the number of KRD events for each group studied
This graph plots the number of kinematic risky driving (KRD) events for each group studied: experienced male (M) and female (F) adult drivers and novice (M and F) teen drivers. Data were collected for a minimum of 21 months. The vertical dotted line in the center marks when the teens received their driver’s licenses. IR stands for Incident Rate, or how many times a KRD event was recorded per 1,600 kilometers (1,000 miles) traveled.
P. Girshon et al/Journal of Adolescent Health 2018

Click here, or on the graph, for a larger image.

Data Dive:

  1. Compare the data for novice drivers (males and females) during the learner period (left) to independent driving.
    1. Which group saw the biggest increase in risky driving events?
    2. Which group saw the smallest change in risky driving events?
  2. These drivers were all volunteers from southwestern Virginia, a rural area near the Appalachian Mountains.
    1. How might the geography of where the volunteers drove affected their driving behaviors?   
    2. How might the data vary in a more densely populated urban area? Why?
    3. Is it possible that volunteers might drive differently than other drivers? How? Do you think this would be a short or long-term effect?
  1. Was this graph difficult to understand? Why?
  1. What would improve this graph or make it easier to read? Explain.


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Power Words

(more about Power Words)

accelerate      To experience a change in velocity (speed).

adolescent     Someone in that transitional stage of physical and psychological development that begins at the onset of puberty, typically between the ages of 11 and 13, and ends with adulthood.

GPS device    Devices that calculate their position (in terms of latitude and longitude) from any place on the ground or in the air. They do this by comparing how long it takes signals from different satellites to reach them.

journal     (in science) A publication in which scientists share their research findings with experts (and sometimes even the public). Some journals publish papers from all fields of science, technology, engineering and math, while others are specific to a single subject. The best journals are peer-reviewed: They send all submitted articles to outside experts to be read and critiqued. The goal, here, is to prevent the publication of mistakes, fraud or sloppy work.

milestone     An important step on the road to stated goal or achievement. The term gets its name from the stone markers that communities used to erect along the side of the road to inform travelers how far they still had to go (in miles) before reaching a town.

sensor     A device that picks up information on physical or chemical conditions — such as temperature, barometric pressure, salinity, humidity, pH, light intensity or radiation — and stores or broadcasts that information. Scientists and engineers often rely on sensors to inform them of conditions that may change over time or that exist far from where a researcher can measure them directly.

Further Reading

Journal: P. Girshon et al. Crash risk and risky driving behavior among adolescents during learner and independent driving periods. Journal of Adolescent Health. Published online July 10, 2018. doi: 10.1016/j.jadohealth.2018.04.012.

Website: Teen Drivers: Get the Facts. The Centers for Disease Control and Prevention.