The Transition to Unsupervised Driving

Background

• Motor vehicle crashes are the leading cause of death for teenagers in the United States

• In 2009, 3,466 teenagers (ages 13-19) were killed in motor vehicle crashes

• The economic cost of crashes involving young drivers is over $34B each year

Graduated Driver Licensing• GDL laws vary widely, but all 50 states and DC have some form

• Optimal GDL laws feature a 3-tiered approach:• Supervised (learner’s permit)• Restricted unsupervised (e.g., nighttime and passenger restrictions)• Full license

• GDL laws allow teen drivers to gain experience behind the wheel while controlling exposure to risks such as:

•Distracting passengers•Nighttime driving•Use of electronic devices

• Largely credited for 42% reduction in fatal crashes of 16-year-old drivers since 1996

The Problem• Parents and other supervisors during the learner’s permit stage generally do a good job creating a safe in-car environment

• Crashes are rare during this first phase

• However, crash rates increase 12 times when teens first begin to drive unsupervised, and teens are 50 percent more likely to crash in their first month of driving than they are after getting a year of experience

• The specific reasons behind this sharp increase in crash risk are not well understood

GDL Stage I: The Permit• Teens can only operate a motor vehicle with a fully- licensed driver in the front passenger seat

• Stage I was examined in previous AAA Foundation research (Goodwin et al., Oct. 2010) which found:

Parents created a safe in-car environment during this stage and incidents were rare

Most of the driving experience teens got was under benign conditions and in routine situations

Teens drove less during Stage I than previously assumed: 1.60 hours/week, spread over 3.2 days

Parental instruction was generally quite basic; training in “higher-order” concepts was rare

GDL Stage II: Key Questions• How do the driving behaviors of newly- unsupervised teens change when they obtain a restricted (provisional) license?

• How do the nature of incidents and the driving environment (internal and external) change when teens begin to drive unsupervised?

• What insight can be gained into the 12-fold crash rate increase seen during the first months of unsupervised driving?

• How can parents better prepare their teens to be solo drivers?

The Study

Published October 2011

Prepared by:

Arthur GoodwinRobert Foss

Natalie O’BrienUNC Highway Safety Research

Center

Available online at www.AAAFoundation.org

Method

•Recruited 50 families in North Carolina as teens applied for learner’s permit

• Following completion of October 2010 study on parental supervision during Stage I, 38 families agreed to continue participating once teen obtained intermediate license

Method (continued)• Installed cameras (triggered by change in g-forces) to capture video clips of the cabin and immediate surroundings in front of and behind vehicle:

• Coded and analyzed nearly 6,000 clips capturing triggering events (e.g., hard braking, swerving, sudden acceleration)• Compared these to 1,750 clips from the initial study (Stage I) that featured the 38 subjects who continued to participate

• Naturalistic – no attempt made to alter behavior of the study participants

• Cameras installed for four months in Stage I, and six months in Stage II

Key Findings and Observations:

• Parent or adult were in the car 3% of Stage II clips compared with 99% of clips during Stage

• Percentage of clips showing young passengers in car didn’t change; however:

• Stage I passengers were mainly siblings• Stage II passengers were often peers

• Driver belt usage remained high (99% of Stage I and 98% of Stage II clips); front passenger belt use declined slightly

• Likelihood of loud music seven times higher in Stage II than Stage I

• One in six Stage II clips had music loud enough to be distracting or mask the sound of horns/sirens

Internal Driving Environment

Key Findings and Observations:

• Regardless of license type, most clips were recorded in the afternoon; however:

• Night driving clips (9 pm – 5 am) were more than twice as likely during Stage II than Stage I

• Stage I clips were most likely to be recorded on weekends; in Stage II they were spread evenly throughout the week

• A greater percentage of Stage II clips occurred in darkness (21% vs. 17% in Stage I)

• Stage II clips 60% more likely to involve wet or rainy conditions compared to Stage I

External Driving Environment

Key Findings and Observations:

• Stage I clips more likely to be triggered by hard acceleration with Stage II clips more often resulted from right turns

•Otherwise, triggering events generally similar

• Few, if any, differences in maximum g-forces were

recorded during Stage I & Stage II triggering events

• Judgment errors and deliberately risky maneuvers became more common once teens began driving unsupervised

• A relatively small number of teens accounted for many of the recorded incidents

Triggering Events/Incidents

Discussion & Recommendations• Driving conditions appear to change between Stages I & II

• More clips recorded at night and in rainy conditions once teens began to drive unsupervised

• Teens may not be adequately prepared for this change: Stage I study found that most supervised practice occurred during the day and in good weather; more practice under varying conditions is therefore needed

• Most (65%) of Stage II clips showed no passengers in the vehicle; however:

• Teens were more likely to be carrying friends during Stage II, and studies show higher crash rates under such circumstances

• Parents should enforce their state’s GDL passenger restrictions (or impose their own)

Discussion & Recommendations•Parents generally absent from Stage II clips ( they were present in only 3%!)

•Remember: just because teens can drive solo with an intermediate license doesn’t mean parents need to disappear or end the training and supervision process •Parents can, and should, stay involved in their teen’s driving

•Significant jump in the likelihood of potentially-distracting music during Stage II suggests that teens should be made aware of the hazards associated with loud music•Notably risky or worrisome incidents were relatively rare during both stages, and only a few differences in behavior were observed when teens began driving unsupervised

Next Steps

Subsequent report will examine certain key issues in greater detail, such as the nature and prevalence of teen distracted driving, and the influences on teen driving that passengers are observed to have.

For more information, go to:

AAAFoundation.org

Established by AAA in 1947, the AAA Foundation for Traffic Safety is a 501(c)(3) not-for-profit, publicly-supported charitable educational and research organization. Dedicated to saving lives and reducing injuries on our roads, the Foundation’s mission is to prevent crashes and save lives through research and education about traffic safety.

The Foundation is supported by donations from AAA/CAA Clubs, AAA/CAA members, and other organizations associated with AAA/CAA.