Trial Outcomes & Findings for Effects of Smoked Marijuana on Risk Taking and Decision Making Tasks (NCT NCT00373399)

NCT ID: NCT00373399

Last Updated: 2018-12-19

Results Overview

A modified version of the Gambling Task (Bechara et al., 1994) was used. Four decks of cards (A-D) were displayed on a computer screen. Volunteers were told that the objective of the game was to win as much money as possible. They were also told that the game entailed a series of card selections from any of the decks, one card at a time, and that they should select cards until instructed to stop. The task was stopped after 100 card selections or after 5 min had elapsed. Data indicate change from baseline in mean number of cards selected from advantageous decks minus number of cards selected from disadvantageous decks as a function of drug condition. Higher numbers indicate better decision making regarding advantageous cards. Planned comparisons using single degrees of freedom, generated by a two-tailed repeated measures analysis of variance (ANOVA), were used to examine the effects of THC concentration (0% vs. 1.8%, 0% vs. 3.9%, and 1.8% vs. 3.9%) on task performance.

Recruitment status

COMPLETED

Study phase

PHASE1

Target enrollment

36 participants

Primary outcome timeframe

3 weeks

Results posted on

2018-12-19

Participant Flow

A total of 36 healthy research volunteers completed this three-session, within-subject outpatient study. Drug treatment was randomized.

Participant milestones

Participant milestones
Measure
0%, Then 1.98%, Then 3.56% THC
A total of 36 volunteers completed this study. Drug treatment was randomized across 3 sessions so each period corresponds to each possible drug treatment.
0%, Then 3.56%, Then 1.98% THC
A total of 36 volunteers completed this study. Drug treatment was randomized across 3 sessions so each period corresponds to each possible drug treatment.
1.98%, Then 0%, Then 3.56% THC
A total of 36 volunteers completed this study. Drug treatment was randomized across 3 sessions so each period corresponds to each possible drug treatment.
1.98%, Then 3.56%, Then 0% THC
A total of 36 volunteers completed this study. Drug treatment was randomized across 3 sessions so each period corresponds to each possible drug treatment.
3.56%, Then 0%, Then 1.98% THC
A total of 36 volunteers completed this study. Drug treatment was randomized across 3 sessions so each period corresponds to each possible drug treatment.
3.56%, Then 1.98%, Then 0% THC
A total of 36 volunteers completed this study. Drug treatment was randomized across 3 sessions so each period corresponds to each possible drug treatment.
Overall Study
STARTED
5
7
4
6
7
7
Overall Study
COMPLETED
5
7
4
6
7
7
Overall Study
NOT COMPLETED
0
0
0
0
0
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Effects of Smoked Marijuana on Risk Taking and Decision Making Tasks

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Total Sample
n=36 Participants
A total of 36 participants completed the study
Age, Categorical
<=18 years
0 Participants
n=5 Participants
Age, Categorical
Between 18 and 65 years
36 Participants
n=5 Participants
Age, Categorical
>=65 years
0 Participants
n=5 Participants
Age, Continuous
25.4 years
STANDARD_DEVIATION 4.0 • n=5 Participants
Sex: Female, Male
Female
16 Participants
n=5 Participants
Sex: Female, Male
Male
20 Participants
n=5 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=5 Participants
Race (NIH/OMB)
Asian
0 Participants
n=5 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=5 Participants
Race (NIH/OMB)
Black or African American
13 Participants
n=5 Participants
Race (NIH/OMB)
White
21 Participants
n=5 Participants
Race (NIH/OMB)
More than one race
2 Participants
n=5 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
n=5 Participants
Region of Enrollment
United States
36 Participants
n=5 Participants

PRIMARY outcome

Timeframe: 3 weeks

Population: All participants who completed the study (N=36) were included in the final analysis.

A modified version of the Gambling Task (Bechara et al., 1994) was used. Four decks of cards (A-D) were displayed on a computer screen. Volunteers were told that the objective of the game was to win as much money as possible. They were also told that the game entailed a series of card selections from any of the decks, one card at a time, and that they should select cards until instructed to stop. The task was stopped after 100 card selections or after 5 min had elapsed. Data indicate change from baseline in mean number of cards selected from advantageous decks minus number of cards selected from disadvantageous decks as a function of drug condition. Higher numbers indicate better decision making regarding advantageous cards. Planned comparisons using single degrees of freedom, generated by a two-tailed repeated measures analysis of variance (ANOVA), were used to examine the effects of THC concentration (0% vs. 1.8%, 0% vs. 3.9%, and 1.8% vs. 3.9%) on task performance.

Outcome measures

Outcome measures
Measure
Inactive Marijuana (0%THC)
n=36 Participants
Task performance for all 36 participants under placebo conditions.
Low Dose Marijuana (1.8% THC)
n=36 Participants
Task performance for all 36 participants under low dose marijuana conditions.
High Dose Marijuana (3.9% THC)
n=36 Participants
Task performance for all 36 participants under high dose marijuana conditions.
Change From Baseline in Iowa Gambling Task Scores [Objective Measure of Decision Making]
3.7 mean number of cards
Standard Deviation 0.8
10.1 mean number of cards
Standard Deviation 3.4
4.4 mean number of cards
Standard Deviation 2.1

Adverse Events

Inactive Marijuana (0%THC)

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Low Dose Marijuana (1.8% THC)

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

High Dose Marijuana (3.9% THC)

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Margaret Haney

New York State Psychiatric Institute

Phone: 646-774-6153

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place