New study aims to create a roadside marijuana impairment test
NCT ID NCT05115513
First seen Jun 27, 2026 · Last updated Jun 27, 2026
Summary
This study, completed by Yale University, tested whether a standardized field test can measure marijuana impairment in drivers. 41 participants who use marijuana regularly completed cognitive tasks and simulated driving after smoking either medium-THC or placebo marijuana. The goal is to develop a reliable test for police to use on the road.
What this could mean
Our plain-language read of the trial. This is informational only — not medical advice or a prediction.
- Active substance
- Marijuana flower with medium THC
- What this could lead to
- If successful, this could lead to a reliable roadside test for marijuana impairment, helping improve road safety.
- What could go wrong
- This is a small, early-phase study (41 participants) that only looks at lab-based tasks, not real driving. Results may not translate to real-world conditions or different populations.
This is an AI summary of the original study and may miss details. Read our disclaimer.
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Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
Olin Neuropsychiatry Research Center
Hartford, Connecticut, 06106, United States