Anxiety, Depression, Insomnia, Pain
Conditions
Keywords
medical marijuana, cannabis, pain, insomnia, depression, anxiety, addiction, dependence, neurocognition, MRI
Brief summary
This study will use a randomized controlled design to test whether patients who use medical marijuana, compared to a waitlist control group, experience a change in health outcomes (relief of symptoms, or adverse health outcomes such as new-onset symptoms of cannabis use disorders, neurocognitive impairments) or brain-based changes.
Detailed description
This trial is a randomized, longitudinal study of medical marijuana (MM) that will: (1) characterize the impact of MM on indices of addiction, such as CUD, escalation of use, tolerance, and withdrawal among those who stop using, (2) assess, via dosing diaries, the effect of MM use patterns on use of other medications, and perception of underlying disease symptomatology, (3) characterize the impact of MM on neurocognitive performance, including executive function, memory, attention, and decision-making and (4) examine evidence for impact of MM on brain structure and function. This study will enroll 200 adults with no prior history of CUD or heavy marijuana use, who express interest in using MM to treat pain, insomnia, anxiety, and/or depression. Participants will be randomly assigned to either an active MM arm (n = 100), or to a waitlist control arm (WLC) (n = 100). Participants will be assessed at baseline, regularly for 3 months, and at a 6-month and 12-month follow-up for MM use behaviors, development of CUD, perception of disease symptomatology, and neurocognitive performance. Urine collected at each visit will be assessed with quantitative assays. MRI scans will be collected to longitudinally investigate possible brain changes associated with MM use.
Interventions
Patients in this group can choose when, where, and how much medical marijuana to use.
Sponsors
Massachusetts General Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
1. Men and women aged 18-65 years, inclusive; 2. Competent and willing to provide written informed consent; 3. Desire to use medical marijuana for self-reported pain, sleep, or affective (mood and/or anxiety including PTSD) symptoms. 4. Not in possession of a medical marijuana card, but expressing intent to get one. 5. Able to communicate in English language.
Exclusion criteria
1. Current daily marijuana use (prior to enrollment) 2. Current substance use disorders (e.g. cocaine, opiate, stimulant). Light to moderate alcohol use is permitted (defined as 16 or less on the AUDIT), and nicotine dependence is permitted because of the high co-use of nicotine and marijuana. Participants cannot meet current SCID criteria for a use disorder on any illicit substance other than nicotine. 3. Pregnant (verified by a urine test). 4. In the opinion of the investigator, not able to safely participate in this study because of any medical or psychological issues (e.g. psychosis) that might compromise their safety.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean Difference in Number of Cannabis Use Disorder Symptoms Averaged Over 2, 4, and 12 Weeks | 2 weeks, 4 weeks, and 12 weeks | The DSM-5 Cannabis Use Disorder (CUD) Checklist will evaluate symptoms of CUD (number of symptoms). The scale ranges from 0-11, with a higher score indicating a greater number of cannabis use disorder symptoms. A trained member of study staff assessed number of CUD symptoms through a structured interview. Each item was scored as 1 if the participant endorsed the symptom, and scored as 0 if they did not endorse the symptom. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates. |
| Mean Difference in Depression Subscale Scores From the HADS Averaged Over 2, 4, and 12 Weeks | 2 weeks, 4 weeks, and 12 weeks | For those with depression symptoms, the depression subscale of the Hospital Anxiety and Depression Scale (HADS) will be used to assess symptoms. The subscale ranges from 0-21, with a higher score indicating worse depression outcomes. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates. |
| Mean Difference in Anxiety Subscale Scores From the HADS Averaged Over 2, 4, and 12 Weeks | 2 Weeks, 4 Weeks, and 12 Weeks | For those with anxiety symptoms, the anxiety subscale from the Hospital Anxiety and Depression Scale (HADS) will be used to assess symptoms. This subscale ranges from 0-21, with higher scores indicating worse anxiety outcomes. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates. |
| Mean Difference in Pain Severity Scores on the BPI Average Over 2, 4, and 12 Weeks | 2 weeks, 4 weeks, and 12 weeks | For those with pain, the Brief Pain Inventory (BPI) severity subscale was used to assess pain symptoms. This scale ranges from 0-10, with a higher score indicating greater pain severity. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates. |
| Mean Difference in Sleep Scores on the AIS Averaged Over 2, 4, and 12 Weeks | 2 weeks, 4 weeks, and 12 weeks | For those with insomnia, the Athens Insomnia Scale (AIS) will be used to assess insomnia symptoms. This scale ranges from 0-24, with higher scores indicating worse sleep outcomes. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Mean Difference in Paired Associates Learning (PAL) Task: Total Errors Scores on the CANTAB Averaged Over 4 and 12 Weeks | 4 weeks and 12 weeks | Total errors were assessed with the Paired Associates Learning (PAL) task, which assesses visual memory and is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range for this measure is 0 to 70 errors. Higher scores indicate that the subject committed more errors (worse performance). Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates. |
| Mean Difference in Spatial Working Memory (SWM) Task: Repetition Errors Scores on the CANTAB Averaged Over 4 and 12 Weeks | 4 weeks and 12 weeks | Repetition errors were assessed with the Spatial Working Memory (SWM) task, which assesses spatial working memory and executive function. It is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range for this measure is 0 to 63 errors. Higher scores indicate that more repetition errors were committed (worse performance). Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates. |
| Mean Difference in Physical Health Scores on the SF-12 Averaged Over 2, 4, and 12 Weeks | 2 weeks, 4 weeks, and 12 weeks | The Short Form-12 Health Survey (SF-12) Physical Health Summary Scale was used to assess self-report of physical health. SF-12 scores are based on an Item Response Theory model, in which they are z-scores rescaled to have a mean of 50 (SD=10) in any typical population. There are no range limits to this measure. Higher scores indicate better physical health functioning. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates. |
| Mean Difference in Verbal Recognition Memory (VRM) Task: Free Recall Memory Scores on the CANTAB Averaged Over 4 and 12 Weeks | 4 weeks and 12 weeks | Free Recall Memory was assessed with the Verbal Recognition Memory task (VRM), which assesses verbal memory. It is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range for this measure is 0 to 18 words recalled. Higher scores indicate that subjects were able to correctly recall more previously studied words. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates. |
| Mean Difference in Verbal Recognition Memory (VRM) Task: d' Scores on the CANTAB Averaged Over 4 and 12 Weeks | 4 weeks and 12 weeks | Discriminability was assessed with the Verbal Recognition Memory task (VRM), which assess verbal memory. It is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). Discriminability scores are based on a transformation of hit and false alarm rates using a signal detection theory (SDT) model.There are no limits for this measure. Higher scores indicate that a subject was able to better discriminate between previously studied and novel words. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates. |
| Mean Difference in Mental Health Scores on the SF-12 Averaged Over 2, 4, and 12 Weeks | 2 weeks, 4 weeks, and 12 weeks | The Short Form 12 Health Survey (SF-12) Mental Health Summary Scale was used to assess self-report of mental health. SF-12 scores are based on an Item Response Theory model, in which they are z-scores rescaled to have a mean of 50 (SD=10) in any typical population. This measure has no range limits. Higher scores indicate better mental health functioning. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates. |
| Mean Difference in Attention Switching Task: Congruency Cost Scores on the CANTAB Averaged Over 4 and 12 Weeks | 4 weeks and 12 weeks | Congruency cost was assessed wth the Attention Switching Task (AST), which assesses attention shifting and executive function via a simple task assessing the direction (pointing left or right) and position (on the left or right side) of an arrow, and is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range of this measure is -1900 to 1900 ms. It is calculated as the difference in the median latency for incongruent trials (i.e., trials where the direction of the arrow differs from the side it appears) minus the median latency for congruent trials (i.e., trials where the direction of the arrow matches the side it appears). Positive values indicate faster responses to congruent trials. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates. |
| Mean Difference in Attention Switching Task: Switching Cost Scores on the CANTAB Averaged Over 4 and 12 Weeks | 4 weeks and 12 weeks | Switching cost was assessed with the Attention Switching Task (AST), which assesses attention shifting and executive function via a simple task assessing the direction (pointing left or right) and position (on the left or right side) of an arrow, and is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range for this measure is -1900 to 1900 ms. It is calculated as the difference in the median latency for blocks of switching trials (i.e., blocks of trials where the response rule switches between indicating the direction of the arrow or the position of the arrow) minus the median latency for blocks of non-switching trials (i.e., blocks of trials where the response rule is always either to indicate the direction of the arrow or the position of the arrow across all trials). Positive scores indicate faster responses to non-switching trials. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates. |
| Mean Difference in Rapid Visual Information Processing (RVP) Task: Discriminability Scores on the CANTAB Averaged Over 4 and 12 Weeks | 4 weeks and 12 weeks | Discriminability was assessed with the Rapid Visual Information Processing (RVP) Task, which assesses sustained attention and is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). Discriminability scores are based on a transformation of response times and accuracy using the EZ-Diffusion model. There are no limits for this measure. Higher scores indicate that subjects can better discriminator between targets and distractors. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Medical Marijuana Arm This group can begin using medical marijuana immediately.
Medical Marijuana: Patients in this group can choose when, where, and how much medical marijuana to use. | 105 |
| Waitlist Control Arm This group agrees to wait 3 months before using medical marijuana. | 81 |
| Total | 186 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Cannabis Use Disorder at Baseline | 11 | 4 |
| Overall Study | Did not obtain MM card | 53 | 0 |
| Overall Study | Lost to Follow-up | 4 | 11 |
Baseline characteristics
| Characteristic | Medical Marijuana Arm | Total | Waitlist Control Arm |
|---|---|---|---|
| Age, Continuous | 37.9 years STANDARD_DEVIATION 14.3 | 37.2 years STANDARD_DEVIATION 14.4 | 36.3 years STANDARD_DEVIATION 14.5 |
| Cannabis Use Frequency Used less than weekly | 82 Participants | 134 Participants | 52 Participants |
| Cannabis Use Frequency Used weekly or more | 23 Participants | 52 Participants | 29 Participants |
| Education Level College 2 Years | 4 Participants | 4 Participants | 0 Participants |
| Education Level College 4 Years | 35 Participants | 61 Participants | 26 Participants |
| Education Level High School | 4 Participants | 10 Participants | 6 Participants |
| Education Level Part College | 16 Participants | 36 Participants | 20 Participants |
| Education Level Part Grad School | 46 Participants | 73 Participants | 27 Participants |
| Education Level Unknown | 0 Participants | 2 Participants | 2 Participants |
| Education Years | 16.6 years STANDARD_DEVIATION 2.3 | 16.5 years STANDARD_DEVIATION 2.5 | 16.3 years STANDARD_DEVIATION 2.7 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 4 Participants | 11 Participants | 7 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 101 Participants | 175 Participants | 74 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Primary Complaint Anxiety/Depression | 46 Participants | 83 Participants | 37 Participants |
| Primary Complaint Insomnia | 22 Participants | 42 Participants | 20 Participants |
| Primary Complaint Pain | 37 Participants | 61 Participants | 24 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 6 Participants | 10 Participants | 4 Participants |
| Race (NIH/OMB) Black or African American | 7 Participants | 14 Participants | 7 Participants |
| Race (NIH/OMB) More than one race | 3 Participants | 6 Participants | 3 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 1 Participants | 4 Participants | 3 Participants |
| Race (NIH/OMB) White | 88 Participants | 152 Participants | 64 Participants |
| Region of Enrollment United States | 105 participants | 186 participants | 81 participants |
| Sex: Female, Male Female | 72 Participants | 122 Participants | 50 Participants |
| Sex: Female, Male Male | 33 Participants | 64 Participants | 31 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 105 | 0 / 81 |
| other Total, other adverse events | 90 / 105 | 60 / 81 |
| serious Total, serious adverse events | 1 / 105 | 0 / 81 |
Outcome results
Primary
Mean Difference in Anxiety Subscale Scores From the HADS Averaged Over 2, 4, and 12 Weeks
For those with anxiety symptoms, the anxiety subscale from the Hospital Anxiety and Depression Scale (HADS) will be used to assess symptoms. This subscale ranges from 0-21, with higher scores indicating worse anxiety outcomes. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates.
Time frame: 2 Weeks, 4 Weeks, and 12 Weeks
Population: The analysis is restricted to the subset of 83 participants out of 186 total who intended to use medical marijuana to address concerns for anxiety and depression.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Anxiety Subscale Scores From the HADS Averaged Over 2, 4, and 12 Weeks | 8.4 units on a scale | Standard Deviation 4.4 |
| Waitlist Control Arm | Mean Difference in Anxiety Subscale Scores From the HADS Averaged Over 2, 4, and 12 Weeks | 8.4 units on a scale | Standard Deviation 3.8 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at weeks 4 and 12 of the study, and for a subject's number of symptoms at baseline.p-value: 0.995% CI: [-0.3, 0.24]Regression, Linear
Primary
Mean Difference in Depression Subscale Scores From the HADS Averaged Over 2, 4, and 12 Weeks
For those with depression symptoms, the depression subscale of the Hospital Anxiety and Depression Scale (HADS) will be used to assess symptoms. The subscale ranges from 0-21, with a higher score indicating worse depression outcomes. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates.
Time frame: 2 weeks, 4 weeks, and 12 weeks
Population: The analysis is restricted to the subset of 83 participants out of 186 total who intended to use medical marijuana to address concerns for anxiety and depression.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Depression Subscale Scores From the HADS Averaged Over 2, 4, and 12 Weeks | 5.4 score on a scale | Standard Deviation 4.3 |
| Waitlist Control Arm | Mean Difference in Depression Subscale Scores From the HADS Averaged Over 2, 4, and 12 Weeks | 5.0 score on a scale | Standard Deviation 3.9 |
Comparison: The mean difference in scale scores between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at weeks 4 and 12 of the study, and for a subject's scale scores at baseline.p-value: 0.595% CI: [-1.4, 0.4]Regression, Linear
Primary
Mean Difference in Number of Cannabis Use Disorder Symptoms Averaged Over 2, 4, and 12 Weeks
The DSM-5 Cannabis Use Disorder (CUD) Checklist will evaluate symptoms of CUD (number of symptoms). The scale ranges from 0-11, with a higher score indicating a greater number of cannabis use disorder symptoms. A trained member of study staff assessed number of CUD symptoms through a structured interview. Each item was scored as 1 if the participant endorsed the symptom, and scored as 0 if they did not endorse the symptom. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates.
Time frame: 2 weeks, 4 weeks, and 12 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Number of Cannabis Use Disorder Symptoms Averaged Over 2, 4, and 12 Weeks | 0.39 score on a scale | Standard Deviation 0.78 |
| Waitlist Control Arm | Mean Difference in Number of Cannabis Use Disorder Symptoms Averaged Over 2, 4, and 12 Weeks | 0.12 score on a scale | Standard Deviation 0.48 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at weeks 4 and 12 of the study, and for a subject's number of symptoms at baseline.p-value: <0.00195% CI: [0.15, 0.4]Regression, Linear
Primary
Mean Difference in Pain Severity Scores on the BPI Average Over 2, 4, and 12 Weeks
For those with pain, the Brief Pain Inventory (BPI) severity subscale was used to assess pain symptoms. This scale ranges from 0-10, with a higher score indicating greater pain severity. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates.
Time frame: 2 weeks, 4 weeks, and 12 weeks
Population: The analysis is restricted to the subset of 61 participants out of 186 total who intended to use medical marijuana to address concerns for pain.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Pain Severity Scores on the BPI Average Over 2, 4, and 12 Weeks | 2.7 score on a scale | Standard Deviation 2.3 |
| Waitlist Control Arm | Mean Difference in Pain Severity Scores on the BPI Average Over 2, 4, and 12 Weeks | 3.3 score on a scale | Standard Deviation 2.5 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at weeks 4 and 12 of the study, and for a subject's number of symptoms at baseline.p-value: 0.9395% CI: [-0.38, 0.39]Regression, Linear
Primary
Mean Difference in Sleep Scores on the AIS Averaged Over 2, 4, and 12 Weeks
For those with insomnia, the Athens Insomnia Scale (AIS) will be used to assess insomnia symptoms. This scale ranges from 0-24, with higher scores indicating worse sleep outcomes. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates.
Time frame: 2 weeks, 4 weeks, and 12 weeks
Population: The analysis is restricted to the subset of 42 participants out of 186 total who intended to use medical marijuana to address concerns for insomnia.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Sleep Scores on the AIS Averaged Over 2, 4, and 12 Weeks | 8.8 score on a scale | Standard Deviation 4.7 |
| Waitlist Control Arm | Mean Difference in Sleep Scores on the AIS Averaged Over 2, 4, and 12 Weeks | 11.6 score on a scale | Standard Deviation 3.7 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at weeks 4 and 12 of the study, and for a subject's number of symptoms at baseline.p-value: <0.00195% CI: [-1.3, -0.43]Regression, Linear
Secondary
Mean Difference in Attention Switching Task: Congruency Cost Scores on the CANTAB Averaged Over 4 and 12 Weeks
Congruency cost was assessed wth the Attention Switching Task (AST), which assesses attention shifting and executive function via a simple task assessing the direction (pointing left or right) and position (on the left or right side) of an arrow, and is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range of this measure is -1900 to 1900 ms. It is calculated as the difference in the median latency for incongruent trials (i.e., trials where the direction of the arrow differs from the side it appears) minus the median latency for congruent trials (i.e., trials where the direction of the arrow matches the side it appears). Positive values indicate faster responses to congruent trials. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates.
Time frame: 4 weeks and 12 weeks
Population: The analysis is restricted to the subset of 162 participants out of 186 total who completed the AST module of the CANTAB at weeks 4 and 12.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Attention Switching Task: Congruency Cost Scores on the CANTAB Averaged Over 4 and 12 Weeks | 63 milliseconds (ms) | Standard Deviation 43 |
| Waitlist Control Arm | Mean Difference in Attention Switching Task: Congruency Cost Scores on the CANTAB Averaged Over 4 and 12 Weeks | 77 milliseconds (ms) | Standard Deviation 50 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at week 12 of the study, and for a subject's score at baseline.95% CI: [-19, 3.5]
Secondary
Mean Difference in Attention Switching Task: Switching Cost Scores on the CANTAB Averaged Over 4 and 12 Weeks
Switching cost was assessed with the Attention Switching Task (AST), which assesses attention shifting and executive function via a simple task assessing the direction (pointing left or right) and position (on the left or right side) of an arrow, and is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range for this measure is -1900 to 1900 ms. It is calculated as the difference in the median latency for blocks of switching trials (i.e., blocks of trials where the response rule switches between indicating the direction of the arrow or the position of the arrow) minus the median latency for blocks of non-switching trials (i.e., blocks of trials where the response rule is always either to indicate the direction of the arrow or the position of the arrow across all trials). Positive scores indicate faster responses to non-switching trials. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates.
Time frame: 4 weeks and 12 weeks
Population: The analysis is restricted to the subset of 162 participants out of 186 total who completed the AST module of the CANTAB at weeks 4 and 12.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Attention Switching Task: Switching Cost Scores on the CANTAB Averaged Over 4 and 12 Weeks | 139 milliseconds (ms) | Standard Deviation 90 |
| Waitlist Control Arm | Mean Difference in Attention Switching Task: Switching Cost Scores on the CANTAB Averaged Over 4 and 12 Weeks | 162 milliseconds (ms) | Standard Deviation 107 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at week 12 of the study, and for a subject's score at baseline.95% CI: [-45.9, -2.2]
Secondary
Mean Difference in Mental Health Scores on the SF-12 Averaged Over 2, 4, and 12 Weeks
The Short Form 12 Health Survey (SF-12) Mental Health Summary Scale was used to assess self-report of mental health. SF-12 scores are based on an Item Response Theory model, in which they are z-scores rescaled to have a mean of 50 (SD=10) in any typical population. This measure has no range limits. Higher scores indicate better mental health functioning. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates.
Time frame: 2 weeks, 4 weeks, and 12 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Mental Health Scores on the SF-12 Averaged Over 2, 4, and 12 Weeks | 44.9 score on a scale | Standard Deviation 11.7 |
| Waitlist Control Arm | Mean Difference in Mental Health Scores on the SF-12 Averaged Over 2, 4, and 12 Weeks | 41.5 score on a scale | Standard Deviation 12.3 |
Secondary
Mean Difference in Paired Associates Learning (PAL) Task: Total Errors Scores on the CANTAB Averaged Over 4 and 12 Weeks
Total errors were assessed with the Paired Associates Learning (PAL) task, which assesses visual memory and is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range for this measure is 0 to 70 errors. Higher scores indicate that the subject committed more errors (worse performance). Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates.
Time frame: 4 weeks and 12 weeks
Population: The analysis is restricted to the subset of 177 participants out of 186 total who completed the PAL module of the CANTAB at weeks 4 and 12.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Paired Associates Learning (PAL) Task: Total Errors Scores on the CANTAB Averaged Over 4 and 12 Weeks | 9.1 Number of errors | Standard Deviation 11.3 |
| Waitlist Control Arm | Mean Difference in Paired Associates Learning (PAL) Task: Total Errors Scores on the CANTAB Averaged Over 4 and 12 Weeks | 9.3 Number of errors | Standard Deviation 11.6 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at week 12 of the study, and for a subject's score at baseline.95% CI: [-1.8, 1.7]
Secondary
Mean Difference in Physical Health Scores on the SF-12 Averaged Over 2, 4, and 12 Weeks
The Short Form-12 Health Survey (SF-12) Physical Health Summary Scale was used to assess self-report of physical health. SF-12 scores are based on an Item Response Theory model, in which they are z-scores rescaled to have a mean of 50 (SD=10) in any typical population. There are no range limits to this measure. Higher scores indicate better physical health functioning. Reported results are an average taken over weeks 2, 4, and 12 to be consistent with the regression model estimates.
Time frame: 2 weeks, 4 weeks, and 12 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Physical Health Scores on the SF-12 Averaged Over 2, 4, and 12 Weeks | 47.1 score on a scale | Standard Deviation 11 |
| Waitlist Control Arm | Mean Difference in Physical Health Scores on the SF-12 Averaged Over 2, 4, and 12 Weeks | 48.2 score on a scale | Standard Deviation 11.8 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at weeks 4 and 12 of the study, and for a subject's score at baseline.95% CI: [-1, 2.5]
Secondary
Mean Difference in Rapid Visual Information Processing (RVP) Task: Discriminability Scores on the CANTAB Averaged Over 4 and 12 Weeks
Discriminability was assessed with the Rapid Visual Information Processing (RVP) Task, which assesses sustained attention and is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). Discriminability scores are based on a transformation of response times and accuracy using the EZ-Diffusion model. There are no limits for this measure. Higher scores indicate that subjects can better discriminator between targets and distractors. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates.
Time frame: 4 weeks and 12 weeks
Population: The analysis is restricted to the subset of 177 participants out of 186 total who completed the RVP module of the CANTAB at weeks 4 and 12.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Rapid Visual Information Processing (RVP) Task: Discriminability Scores on the CANTAB Averaged Over 4 and 12 Weeks | 0.076 score on a scale | Standard Deviation 0.047 |
| Waitlist Control Arm | Mean Difference in Rapid Visual Information Processing (RVP) Task: Discriminability Scores on the CANTAB Averaged Over 4 and 12 Weeks | 0.058 score on a scale | Standard Deviation 0.044 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at week 12 of the study, and for a subject's score at baseline.95% CI: [-0.007, 0.011]
Secondary
Mean Difference in Spatial Working Memory (SWM) Task: Repetition Errors Scores on the CANTAB Averaged Over 4 and 12 Weeks
Repetition errors were assessed with the Spatial Working Memory (SWM) task, which assesses spatial working memory and executive function. It is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range for this measure is 0 to 63 errors. Higher scores indicate that more repetition errors were committed (worse performance). Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates.
Time frame: 4 weeks and 12 weeks
Population: The analysis is restricted to the subset of 177 participants out of 186 total who completed the ? module of the CANTAB at weeks 4 and 12.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Spatial Working Memory (SWM) Task: Repetition Errors Scores on the CANTAB Averaged Over 4 and 12 Weeks | 26.4 Number of errors | Standard Deviation 18.4 |
| Waitlist Control Arm | Mean Difference in Spatial Working Memory (SWM) Task: Repetition Errors Scores on the CANTAB Averaged Over 4 and 12 Weeks | 30.0 Number of errors | Standard Deviation 19.8 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at week 12 of the study, and for a subject's score at baseline.95% CI: [-7.4, 0.3]
Secondary
Mean Difference in Verbal Recognition Memory (VRM) Task: d' Scores on the CANTAB Averaged Over 4 and 12 Weeks
Discriminability was assessed with the Verbal Recognition Memory task (VRM), which assess verbal memory. It is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). Discriminability scores are based on a transformation of hit and false alarm rates using a signal detection theory (SDT) model.There are no limits for this measure. Higher scores indicate that a subject was able to better discriminate between previously studied and novel words. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates.
Time frame: 4 weeks and 12 weeks
Population: The analysis is restricted to the subset of 171 participants out of 186 total who completed the VRM module of the CANTAB at weeks 4 and 12.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Verbal Recognition Memory (VRM) Task: d' Scores on the CANTAB Averaged Over 4 and 12 Weeks | 2.6 score on a scale | Standard Deviation 0.8 |
| Waitlist Control Arm | Mean Difference in Verbal Recognition Memory (VRM) Task: d' Scores on the CANTAB Averaged Over 4 and 12 Weeks | 2.7 score on a scale | Standard Deviation 0.7 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at week 12 of the study, and for a subject's score at baseline.95% CI: [-0.2, 0.1]
Secondary
Mean Difference in Verbal Recognition Memory (VRM) Task: Free Recall Memory Scores on the CANTAB Averaged Over 4 and 12 Weeks
Free Recall Memory was assessed with the Verbal Recognition Memory task (VRM), which assesses verbal memory. It is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The range for this measure is 0 to 18 words recalled. Higher scores indicate that subjects were able to correctly recall more previously studied words. Reported results are an average taken over weeks 4 and 12 to be consistent with the regression model estimates.
Time frame: 4 weeks and 12 weeks
Population: The analysis is restricted to the subset of 175 participants out of 186 total who completed the free recall VRM module of the CANTAB at weeks 4 and 12.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Medical Marijuana Arm | Mean Difference in Verbal Recognition Memory (VRM) Task: Free Recall Memory Scores on the CANTAB Averaged Over 4 and 12 Weeks | 8.9 Total recalled | Standard Deviation 2.7 |
| Waitlist Control Arm | Mean Difference in Verbal Recognition Memory (VRM) Task: Free Recall Memory Scores on the CANTAB Averaged Over 4 and 12 Weeks | 8.5 Total recalled | Standard Deviation 2.8 |
Comparison: The mean difference in number of symptoms between the MM and WLC groups was estimated via a linear model with a dummy-coded contrast (0 for WLC, 1 for MM). The model adjusted for change at week 12 of the study, and for a subject's score at baseline.95% CI: [-0.2, 1]