Summary of findings comparing intramuscular botulinum toxin to placebo in patients with shoulder spasticity.
| Outcomes | Illustrative Comparative Risks* (95% CI) | Relative Effect (95% CI) | No. Participants (studies) | Quality of Evidence (GRADE) | Comments | |
|---|---|---|---|---|---|---|
| Assumed Risk Control | Corresponding Risk Intramuscular Botulinum toxin | |||||
| Pain (0–10 cm VAS or 0–10 VRS at 12–24 wks | Mean pain (0–10 cm VAS): pain at 6–12 wks in control groups was 4.8 | Mean pain (0–10 cm VAS): pain at 6–12 wks in intervention groups was 1.22 lower (0.07 to 2.37 lower) | NA | 76 (3) | + + − − Low1,2 | Absolute risk difference 12% (95% CI 1% to 24%); relative percentage change 25% (95% CI 1% to 49%); NNT benefit = 4 (95% CI 2 to 102) |
| No. adverse events (followup 4–24 wks) | 235 per 1000 | 343 per 1000 (150 to 790) | RR 1.46 (0.64 to 3.36) | 65 (3) | + + − − Low1,2 | Absolute risk difference 9% (95% CI −22% to 39%); relative percentage change 46% (95% CI −36% to 226%); NNT harm = not estimable3 |
| Disability/function | Not reported in any study | Not reported in any study | Not estimable | — | NA | NA |
| Withdrawals due to adverse events | Not reported in any study | Not reported in any study | Not estimable | — | NA | NA |
| Serious adverse events | Not reported in any study | Not reported in any study | Not estimable | — | NA | NA |
* The basis for the assumed risk (e.g., the median control group risk across studies) is provided in footnotes. The corresponding risk (95% is based on the assumed risk in the comparison group and the relative effect of the intervention (95% CI).
↵1 Allocation sequence generation and allocation concealment was not described in some studies.
↵2 Sample sizes were small for all studies, making estimates liable to error.
↵3 95% CI includes both positive and negative numbers, therefore NNT harm is not estimable.
GRADE Working Group grades of evidence: High quality: further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: further research is likely to have an important influence on our confidence in the estimate of effect and may change the estimate. Low quality: further research is very likely to have an important influence on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. RR: risk ratio; NA: not applicable; VAS: visual analog scale; VRS: verbal rating scale; NNT: number needed to treat.