Summary of findings 6. N‐acetylcysteine compared to placebo for cannabis dependence.
| N‐acetylcysteine compared to placebo for cannabis dependence | |||||
| Patient or population: cannabis dependence Setting: outpatient Intervention: N‐acetylcysteine Comparison: placebo | |||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | |
| Risk with placebo | Risk with N‐acetylcysteine | ||||
| Participants abstinent at end of treatment | Study population |
RR 0.89 (0.59 to 1.35) |
302 (1 RCT) | ⊕⊕⊝⊝ Lowa | |
| 242 per 1000 | 215 per 1000 (143 to 326) | ||||
| Participants experiencing adverse effects | Study population |
RR 0.94 (0.71 to 1.23) |
418 (2 RCTs) | ⊕⊕⊕⊝ Moderateb | |
| 329 per 1000 | 309 per 1000 (233 to 404) | ||||
| Participants withdrawn due to adverse effects | Study population |
RR 3.00 (0.12 to 72.15) |
116 (1 RCT) | ⊕⊕⊝⊝ Lowa | |
| 0 per 1000 | 0 per 1000 (0 to 0) | ||||
| Completion of scheduled treatment | Study population |
RR 1.06 (0.93 to 1.21) |
418 (2 RCTs) | ⊕⊕⊕⊝ Moderateb | |
| 652 per 1000 | 691 per 1000 (607 to 789) | ||||
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; RCT: randomised controlled trial; RR: risk ratio. | |||||
| GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | |||||
aDowngraded two levels for imprecision: single study, few events.
bDowngraded one level for imprecision: very few events and small group sizes.