Outcome
Type |
Measure |
Description |
Time frame |
Safety issue |
Primary |
Enrollment rate |
proportion of screened subjects eligible and willing to participate |
Week 8 |
|
Secondary |
Retention rates of participants |
Retention rate was determined as the proportion of completed study visits. |
Week 8 |
|
Secondary |
Medication adherence measured by pill count. |
Proportion of pills taken as prescribed. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Incidence of Treatment-Emergent Adverse Events among participants as assessed by participant self-report on a structured questionnaire of common varenicline side effects. |
Participants self-reported adverse events using a structured questionnaire of common varenicline symptoms. The questionnaire was developed ad hoc. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Incidence of Treatment-Emergent psychiatric symptoms reported by participants as measured by the MINI International Neurospsychiatric Interview |
To address psychiatric symptoms, the MINI International Neuropsychiatric Interview (M.I.N.I) was used. The Mini-International Neuropsychiatric Interview (M.I.N.I.) is a short structured diagnostic interview, developed jointly by psychiatrists and clinicians in the United States and Europe, for DSM-IV and ICD-10 psychiatric disorders. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Cannabis craving as measured by the marijuana craving questionnaire. |
The Marijuana Craving Questionnaire (MCQ) is a valid and reliable, self-report instrument with 47 items rated on a 7-point Likert scale from 1 (strongly disagree) to 7 (strongly agree). The 47 items are grouped by certain characteristics and the score of each of resulting groups correlates to the intensity of the four craving dimensions (compulsivity, emotionality, expectancy, and purposefulness). Total possible scores range from 47- 329. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Cannabis withdrawal as measured by the marijuana withdrawal checklist. |
Cannabis withdrawal is measured by the 15-item version of the marijuana withdrawal checklist. In the marijuana withdrawal checklist, respondents rate each symptom experienced during their most recent period of marijuana abstinence, based on a 4-point scale where 0 = none, 1 = mild, 2 = moderate, and 3 = severe. A total MWC score is obtained by summing the severity ratings. Total scores range from 0 - 45, with 0 as the least severe score and 45 as the highest score. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Quantity of past two week cannabis use as measured by the timeline follow back method. |
Measured using the timeline follow-back method, a method in which participants use a physical calendar to note the number of days over a specified period of time during which they used cannabis. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Quantity of past two week tobacco use as measured by the timeline follow back method. |
Measured using the timeline follow-back method, a method in which participants use a physical calendar to note the number of days over a specified period of time during which they used tobacco. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Frequency of past two week cannabis use as measured by percentage of days self-reported in the timeline follow-back method. |
Measured using the timeline follow-back method, a method in which participants use a physical calendar to note the number of days over a specified period of time during which they used cannabis. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Frequency of past two week tobacco use as measured by percentage of days self-reported in the timeline follow-back method. |
Measured using the timeline follow-back method, a method in which participants use a physical calendar to note the number of days over a specified period of time during which they used tobacco. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Cannabis abstinence as measured by urine toxicology test. |
Cannabis abstinence was measured by a urine toxicology test, defined as a tetrahydrocannabinol level less than 50 ng/ml. Urine samples were analyzed at a commercial laboratory. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Biochemically verified tobacco abstinence as measured by a Bedfont Smokerlyzer carbon monoxide reader. |
Tobacco abstinence was assessed via a Bedfont Smokerlyzer carbon monoxide reader and operationalized as a reading of less than 8 p.p.m. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Cannabis abstinence as measured by timeline follow back method. |
Measured using the timeline follow-back method, a method in which participants use a physical calendar to note the number of days over a specified period of time during which they used cannabis. Abstinence was defined as self-reported two-week abstinence. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Tobacco abstinence as measured by timeline follow back method. |
Measured using the timeline follow-back method, a method in which participants use a physical calendar to note the number of days over a specified period of time during which they used tobacco. Abstinence was defined as self-reported two-week abstinence. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Mean expired carbon monoxide as measured by Bedfont Smokealyzer carbon monoxide reader. |
Measured by Bedfont Smokealyzer carbon monoxide reader. |
Weeks 2, 4, 6, and 8. |
|
Secondary |
Incidence of Treatment-Emergent suicidal ideation reported by participants as measured by the Columbia Suicide Severity Rating Scale. |
The Columbia Suicide Severity Rating Scale contains 6 "yes" or "no" questions in which respondents are asked to indicate whether they have experienced several thoughts or feelings relating to suicide over the past month and behaviors over their lifetime and past 3 months. An answer of "yes" to any of the six questions may indicate a need for referral to a trained mental health professional and an answer of "yes" to questions to the last three questions (4,5, 6) indicate high-risk. |
Weeks 2, 4, 6, and 8. |
|