ESTIMATED BENEFIT | ||||
---|---|---|---|---|
INDICATION | CANNABINOIDS | CONTROL (PLACEBO UNLESS INDICATED) | NNT | GRADE QUALITY OF EVIDENCE |
Chronic pain (median follow-up 4 wk) | ||||
• ≥ 30% reduction in chronic (neuropathic plus cancer) pain* | 39% | 30% | 11 | Very low |
• ≥ 30% reduction in neuropathic pain | 38% | 30% | 14 | Very low |
• ≥ 30% reduction in palliative pain | 30% | 23% | NS (approximately 15)† | Very low |
• Change in chronic pain scales (possible score 0–10)‡ | Baseline: approximately 6 Decrease: 1.2–1.6 | Baseline: approximately 6 Decrease: 0.8 | NA | Very low |
Chemotherapy-induced nausea and vomiting (median follow-up 1 d) | ||||
• Control of nausea and vomiting (cannabinoids vs placebo) | 47% | 13% | 3 | Moderate |
• Control of nausea and vomiting (cannabinoids vs neuroleptics) | 31% | 16% (vs neuroleptics) | 7 | Low |
Spasticity (median follow-up 6 wk) | ||||
• Global impression of change | 50% | 35% | 7 | Low |
• ≥ 30% improvement in spasticity | 35% | 25% | 10 | Low |
• Change in spasticity (possible score 0–10)‡ | Baseline: 6.2 Decrease: 1.3–1.7 | Baseline: 6.2 Decrease: 1.0 | NA | Very low |
GRADE—Grading of Recommendations Assessment, Development and Evaluation, NA—not applicable, NNT—number needed to treat, NS—not statistically significant. Data from accompanying systematic review by Allan et al (page e78).12
↵* Meta-analysis results included 13 studies on neuropathic pain and 2 studies on cancer pain.
↵† Confidence intervals suggest that benefit is likely (risk ratio = 1.34, 95% CI 0.96 to 1.86), so estimated NNT provided.
↵‡ Scales are visual analogue scales or numeric rating scales with higher scores indicating worse pain or spasticity. Changes with cannabinoids are given as a range based on varying results.