Cannabis UseNAACIDNCT06255054
Novel Approaches to Assessing Cannabis Impaired Driving (NAACID)
An observational study of Cannabis Use, run by Colorado School of Public Health at 1 site in United States.
Trial summary
Researchers at the University of Colorado Anschutz Medical Campus, Colorado School of Public Health, and Injury \& Violence Prevention Center want to learn more about how people are affected by cannabis in different ways. Read more about this study
- Who is it for?
- Ages 25 to 55 years
- Conditions the study is for
- Cannabis Use
- How many people
- 207 participants
- Where
- 1 siteUnited States
- Study dates
- 20 Jun 2020to 14 Sep 2024
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 25 to 55 years
- All sexes
- Adult
Study population: Potential participants will be recruited from the general population.
Who may be able to join
- The following are inclusion criteria for participants to be enrolled in any of the four phases of the study:
- Participants who are ≥21 years old and ≤55 years old
- Participants who are able to provide written, informed consent
- Participants with active healthcare coverage (including health insurance, Medicaid, etc.)
- Participants who are willing to complete up to two in-person study visits (one for Phases 1 \& 2, and two for Phases 3 \& 4), including up to two urine drug screens, two alcohol breathalyzer tests, and one urine pregnancy test (if applicable)
- Participants who agree to refrain from using non-prescription psychotropic drugs (e.g., ecstasy), hallucinogens, and synthetic cannabinoids during the study
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- Participants who agree to refrain from drinking >3 alcoholic drinks the day prior to the data collection study visit (the single visit for Phases 1 \& 2, and the second visit for Phases 3 \& 4)
- Participants who agree to refrain from using any cannabis products for at least 8 hours prior to the data collection study visit (the single visit for Phases 1 \& 2, and the second visit for Phases 3 \& 4)
- Participants who are willing to provide and use their own cannabis product that has been procured from a licensed dispensary, is labeled with THC potency, and contains <2% CBD (cannabis use groups only; the single visit for Phases 1 \& 2, and the second visit for Phases 3 \& 4)
- Participants who agree to have a sober driver pick them up after the data collection study visit (cannabis use groups only; the single visit for Phases 1 \& 2, and the second visit for Phases 3 \& 4)
- Participants who take at least 2 inhalations ("hits") during their typical inhalational (smoking/vaporizing) sessions, or ingest at least 5 mg of THC when they consume edible cannabis products (cannabis use groups only)
- Participants who are willing to provide a sample of their cannabis to be independently tested for potency and terpene content (Phases 1, 3 \& 4 only)
Who cannot join
- The following are exclusion criteria for participants to be enrolled in any of the four phases of the study:
- Prisoners
- Participants who have nocturnal schedules (e.g., work night shifts)
- Participants with a history of abuse or addiction to substances other than cannabis (e.g., prescription and non-prescription pharmaceuticals, alcohol, or illicit drugs)
- Participants who have expressed an interest in substance abuse treatment within the 60 days prior to study enrollment
- Participants who report consuming an average of >3 alcoholic drinks per day in the 30 days prior to study enrollment
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- Participants with any past or current diagnosis of schizophrenia, narcolepsy, heart disease, epilepsy, or a traumatic brain injury
- Participants who are currently experiencing untreated bipolar disorder, major depression, sleep apnea, or other uncontrolled medical conditions as determined by the investigators (e.g., hypertension)
- Participants with a known balance or gait disorder
- Participants with color blindness (Phase 2 only)
- Participants who currently wear hard contact lenses for vision correction (Phase 2 only)
- Participants who have donated 450 mL or more of blood in the two weeks prior to study enrollment
- Participants who are pregnant or breastfeeding (female participants only)
- Participants who report never using cannabis before in their lifetime (Phases 1 \& 2 only)
- Participants with a history of clinically significant adverse event(s) associated with cannabis intoxication (e.g., lightheadedness, nausea, dizziness, etc., cannabis use groups only)
- Participants with uncorrected visual acuity disorder, defined as binocular vision worse than 20/40 (Phases 2, 3 \& 4 only; determined at screening)
- Participants with a body mass index >40 kg/m2 (determined at screening)
- Participants with a positive breath alcohol test (breathalyzer) at screening
- Participants who are otherwise unsuitable for inclusion in the study, based on the opinion of the investigator
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Novel Approaches to Assessing Cannabis Impaired Driving
Researchers at the University of Colorado Anschutz Medical Campus, Colorado School of Public Health, and Injury \& Violence Prevention Center want to learn more about how people are affected by cannabis in different ways. The study will use a driving simulator to compare the driving performance of adults who use cannabis daily, occasionally or have not recently used cannabis.
- Conditions
- Cannabis Use
- Keywords
- Driving Impairment
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Non-Users | People who do not use cannabis. | |
| Daily Flower Users | People who use cannabis flower daily. | |
| Daily Concentrate Users | People who use cannabis concentrate products daily. | |
| Occasional Flower Users | People who use cannabis flower at least once a month and no more than three times per week. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Driving Impairment
SDLP (standard deviation of lateral position) is measured by our Advanced NADS minisim
Measured: 5 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Feb 2024
- Study start20 Jun 2020
- Primary completion14 Sep 2024
- Study completion14 Sep 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Cannabis UseStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Ecologic or community
- Time perspective
- Prospective
- Enrolment
- 207 participants (actual)
Sponsor and investigators
- Lead sponsor
- Colorado School of Public Health
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Ashley Brooks-Russell, Colorado School of Public Health
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06255054
- Sponsor's protocol ID
- ColoradoSPH
- Acronym
- NAACID
- Status last verified
- Apr 2026
- First submitted
- 21 Jul 2023
- Last updated
- 23 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 23 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Novel Approaches to Assessing Cannabis Impaired Driving
- ClinicalTrials.gov ID
- NCT06255054
- Acronym / sponsor ID
- NAACID / ColoradoSPH
- Conditions
- Cannabis Use
- Keywords
- Driving Impairment
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 207 participants (actual)
- Lead sponsor
- Colorado School of Public HealthUniversity, hospital or other
- Study start
- 20 Jun 2020 (actual)
- Primary completion
- 14 Sep 2024 (actual)
- Study completion
- 14 Sep 2024 (actual)
- First posted
- 12 Feb 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Researchers at the University of Colorado Anschutz Medical Campus, Colorado School of Public Health, and Injury \& Violence Prevention Center want to learn more about how people are affected by cannabis in different ways. The study will use a driving simulator to compare the driving performance of adults who use cannabis daily, occasionally or have not recently used cannabis.
Study design
- Observational model
- Ecologic or community
- Time perspective
- Prospective
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Non-Users | – | –People who do not use cannabis. |
| Daily Flower Users | – | –People who use cannabis flower daily. |
| Daily Concentrate Users | – | –People who use cannabis concentrate products daily. |
| Occasional Flower Users | – | –People who use cannabis flower at least once a month and no more than three times per week. |
Who may qualify
- Ages
- 25 to 55 years
- Sex
- All
- Age groups
- Adult
- Study population
- Potential participants will be recruited from the general population.
Key inclusion criteria (12 listed)
- The following are inclusion criteria for participants to be enrolled in any of the four phases of the study:
Key exclusion criteria (19 listed)
- The following are exclusion criteria for participants to be enrolled in any of the four phases of the study:
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Driving Impairment
Time frame: 5 years
SDLP (standard deviation of lateral position) is measured by our Advanced NADS minisim
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Apr 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Cannabis Use, run by Colorado School of Public Health at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 12 inclusion and 19 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 23 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Driving Impairment (time frame: 5 years). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Apr 2026.