Table 4.
Methodological quality of studies of effect of chronic cannabis use on salience processing
| Study | Defined study population | Comparability of subjects | Adequate exposure | Control | Outcome Measurement | Statistical analysis | Excluded/adjustment for tobacco confounding? | Funding or sponsorship |
|---|---|---|---|---|---|---|---|---|
| Charboneau et al. (2013) | ✓ Non-treatment seeking cannabis dependent users (8hrs abstinent) |
✓ Within subject |
✓ Met MINI criteria for cannabis dependence; positive urine cannabis screen |
✓ Within Subject |
✓ - Cannabis craving score - Regional brain activation |
✓ - Friedman test - Spearman correlation |
✕ Not specified |
✓ Declared |
| Somaini et al. (2012) | ✓ Cannabis dependent active users |
✓ | ✓ Met DSM IV criteria for cannabis dependence; urine screening at baseline, and twice weekly thereafter. |
✓ Abstinent cannabis users; non-users |
✓ - Evaluation of affective images - Regional brain activation |
✓ - One-way ANOVA |
✓ Participants abstained from tobacco for 12hrs before study |
✕ Not specified |
| Filbey et al. (2009) | ✓ Regular cannabis users (72hrs abstinent) |
✓ Within subject |
✓ Self-reported cannabis use of at least four times/week for previous 6 months |
✓ Within subject |
✓ - Cannabis craving - Regional brain activation |
✓ - Multiple linear regression analysis |
✕ Not specified |
✓ Declared |
| Grant et al. (2012) | ✓ Non-treatment seeking users |
✓ | ✓ Self-reported cannabis use of ±3.1 times/week for previous 12 months |
✓ Non-users |
✓ - Performance on attentional processing task |
✓ - ANOVA |
✕ No |
✓ Declared |
| Kober et al. (2014) | ✓ Treatment seeking cannabis dependent users |
✓/✕ Age/sex matched. No info on psychiatric illness, additional substance use, or psychotropic medication for users. |
✓ Met DSM IV SCID criteria for cannabis dependence; weekly self-report and urine drug screening |
✓ Non-users |
✓ - Performance on attentional processing task |
✓ - Random effects analysis |
✕ No |
✓ Declared |
| Wölfling et al. (2008) | ✓ Chronic heavy cannabis dependent users (12hrs abstinent) |
✓/✕ Demographic characteristics matched. More tobacco smokers in the dependent users group. |
✓ Met ICD 10 criteria for cannabis dependence |
✓ Non-users |
✓ - Cannabis craving scores - Arousal |
✓ - One-way ANOVA |
✓ Participants abstained from tobacco for 2hrs before study |
✕ Not specified |
| Gruber et al. (2005) | ✓ Heavy cannabis users |
✓ | ✓ Self-report; positive urine cannabis screen |
✓ Non-users |
✓ - Performance on attentional processing task - Regional brain activation |
✓ - Random effects t test analysis |
✕ Not specified |
✓ Declared |
| Eldreth et al. (2004) | ✓ Heavy cannabis users (25d abstinent) |
✓ | ✓ Screened with DUSQ, ASI, DIS, DSM IV, self-report, and positive urine drug screen for cannabis |
✓ Non-users |
✓ - Performance on attentional processing task - Regional brain activation |
✓ - Random effects two-sample t test |
✓ Participants abstained from tobacco for 3hrs before study |
✓ Declared |
DSM IV – Diagnostic and Statistical Manual of Mental Disorders; SCID – Structured Clinical Interview for DSM Disorders; ICD 10 – International Statistical Classification of Diseases and Related Health Problems; DUSQ – Drug Use Survey Questionnaire, ASI – Addiction Severity Index, DIS – Diagnostic Interview Schedule; ANOVA – Analysis of variance