Assessing how cannabis affects driving impairment

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This study involves approximately 300 volunteers who will smoke either active cannabis, a placebo, or no substance at all. Participants will then undergo a driving test while being observed by California Highway Patrol officers to determine their level of impairment. The study aims to validate existing behavioral assessments used by law enforcement for detecting cannabis-induced driving impairment against a comprehensive driver evaluation. This research is conducted in a controlled environment to better understand the effects of cannabis on driving abilities.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Possessing a valid California driver's license
* Cannabis use in the past six months
* Willing and able to abstain from alcohol, cannabis, and other recreational drugs for 24 hours prior to scheduled participation
* Willing and able to avoid driving and operating heavy machinery for at least four hours after participation
* Residence within approximately 15 miles of the study site
* Possessing the capacity to provide informed consent

Exclusion Criteria:

* Completion of a roadside sobriety test during the previous 12 months
* Physical or psychological conditions that can be exacerbated by cannabis use, or for which cannabis use is contraindicated
* Potential presence of Cannabis Use Disorder as assessed by a modified version of the Cannabis Use Disorder Identification Test
* Potential presence of Substance Use Disorder as assessed by a modified version of the Drug Abuse Screening Test
* Pregnancy or breastfeeding reported
* Unwillingness to be transported by taxi
* Having been convicted of Driving Under the Influence (DUI) within five years prior to scheduled participation
* Parole or probation status
* One or more felony convictions on record involving aggressive or dangerous criminal activity
* Any of the following at the time of the experimental session: breath alcohol content of .01% or greater; positive pregnancy test; cannabis consumption considered unsafe following medical checkup by the study nurse; or driving test behavior considered hazardous by the driving examiner

Where it's running

• California Department of Motor Vehicles Headquarters
  Sacramento, California, United States Recruiting

Study contacts

• Principal investigator: Bayliss J Camp, PhD — California Department of Motor Vehicles
• Study coordinator: Dario LM Sacchi, PhD
• Email: dario.sacchi2@dmv.ca.gov
• Phone: (916) 818 5312

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.