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Preventing Impaired Driving Among Adolescents

A Pilot Trial to Prevent Intoxicated and Impaired Driving Among Adolescents

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04959461
Acronym
webCHAT
Enrollment
198
Registered
2021-07-13
Start date
2022-01-01
Completion date
2025-08-31
Last updated
2026-03-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Substance-Related Disorders

Keywords

impaired driving

Brief summary

The primary goal of this project is to evaluate the efficacy of webCHAT, a single-session web-intervention, on reducing impaired driving among adolescents receiving behind-the-wheel training at driver education programs.

Detailed description

Alcohol and marijuana (AM) are the most commonly used substances among adolescents in the U.S. The consequences of AM use are significantly higher relative to use of either substance alone. This study builds on effective interventions that have demonstrated reductions in alcohol and/or marijuana use and reduced consequences one year later, and proposes to adapt one of those interventions, CHAT, to the web (web-CHAT). The investigators will evaluate the efficacy of web-CHAT among 15.5-17-year-old adolescents (n=150) recruited when teen participants are attending behind-the-wheel training. The study has the potential to promote public welfare by improving adolescent health outcomes and reducing risky driving behaviors that can have substantial monetary and social costs, as well as by providing unique insight into what mediates reduced risky driving attitudes behaviors among those in the intervention. The study is innovative because it is for both youth who are at risk for substance use as well as those who are not, and it is delivered during a teachable moment when adolescents receive driver's education. Finally, this study can provide unique insights about the efficacy of web-CHAT to reduce marijuana initiation, use, and risky driving attitudes in the context of a changing marijuana policy climate. A 3-year study is proposed to test the feasibility of research procedures in a driver education setting and pilot the efficacy of web-CHAT. The investigators will test whether web-CHAT reduces alcohol and/or marijuana initiation or use compared to teens in UC, at three and six-month follow-up.

Interventions

BEHAVIORALwebCHAT

A self-guided, single session web intervention that utilizes a motivational interviewing style to prevent impaired driving

BEHAVIORALUsual Care

6 hours of driver education

Sponsors

Stanford University
Lead SponsorOTHER
National Institute on Alcohol Abuse and Alcoholism (NIAAA)
CollaboratorNIH

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Intervention model description

Teen participants will be randomized to a single-session, self-guided web-intervention called webCHAT or usual care after completing an online baseline survey. Participants will complete follow-up surveys 3 and 6-months after baseline.

Eligibility

Sex/Gender
ALL
Age
15 Years to 17 Years
Healthy volunteers
Yes

Inclusion criteria

* 15.5-17 year olds enrolled in driver education school * Access to a computer or smartphone * Within one month of taking their driver's licensing exam

Exclusion criteria

* Under 15.5 or over 17 years old * Not enrolled in one of the participating schools * Non-English speaking

Design outcomes

Primary

MeasureTime frameDescription
Alcohol and/or Cannabis UseBaseline through 6-month-follow-upTotal number of participants who self-reported an increased frequency of using the specified substance or substance combination in the past 3 months at 3- and/or 6-month-follow-up when compared to baseline, as denoted by a binary variable (1 = increased frequency; 0 = maintained or decreased frequency)

Secondary

MeasureTime frameDescription
Driving Under the InfluenceAssessed at 6 month follow-upNumber and percentage of participants who drove under the influence of alcohol and/or cannabis in the past 90 days
Riding With Impaired DriverBaseline through month 6Total number of participants who self-reported an increased frequency of riding with an impaired driver (RWID) who had consumed the specified substance or combination of substances in the past 3 months at 3- and/or 6-month-follow-up when compared to baseline as indicated by a binary (1 = increased frequency; 0 = maintained or reduced frequency)
Perceived Descriptive Norms6 month follow-upPercentage of their peers (0% of their peers-100% of their peers) participants believe have consumed alcohol, cannabis, or both simultaneously in past month

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORKaren Osilla, PhD

Professor

Baseline characteristics

Characteristic
Age, Categorical
<=18 years
198 Participants
Age, Categorical
>=65 years
0 Participants
Age, Categorical
Between 18 and 65 years
0 Participants
CRAFFT Screener
<1
46 Participants
CRAFFT Screener
>=1
99 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
5 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
189 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Lifetime History of Riding with Impaired Driver
Did Not Ride with Impaired Driver
73 Participants
Lifetime History of Riding with Impaired Driver
Rode with Impaired Driver
34 Participants
Lifetime Substance Use
Alcohol
40 Participants
Lifetime Substance Use
Cannabis
29 Participants
Lifetime Substance Use
No Lifetime History
79 Participants
Lifetime Substance Use
Simultaneous Cannabis and Alcohol Use
10 Participants
Race (NIH/OMB)
American Indian or Alaska Native
2 Participants
Race (NIH/OMB)
Asian
3 Participants
Race (NIH/OMB)
Black or African American
2 Participants
Race (NIH/OMB)
More than one race
13 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
1 Participants
Race (NIH/OMB)
Unknown or Not Reported
2 Participants
Race (NIH/OMB)
White
158 Participants
Sex/Gender, Customized
Gender Identity
Female
64 Participants
Sex/Gender, Customized
Gender Identity
Male
79 Participants
Sex/Gender, Customized
Gender Identity
Other
0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 1060 / 92
other
Total, other adverse events
0 / 1060 / 92
serious
Total, serious adverse events
0 / 1060 / 92

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 28, 2026