Summary of findings for the main comparison. Botulinum toxin versus observation.
| Botulinum toxin versus observation in people with sixth nerve palsy | ||||||
| Participant or population: people with sixth nerve palsy Setting: hospital Intervention: botulinum toxin Comparison: observation | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with observation | Risk with botulinum toxin | |||||
| Improvement in ocular motility (ocular alignment ≤ 10 prism dioptres). Follow‐up to 4 months |
800 per 1,000 | 952 per 1,000 (768 to 1,000) | RR 1.19 (0.96 to 1.48) | 47 (1 RCT) | ⊕⊕⊝⊝ LOW 1 | |
| Achievement of binocular single vision (fusion and stereopsis present). Follow‐up to 4 months |
800 per 1,000 | 952 per 1,000 (768 to 1,000) | RR 1.19 (0.96 to 1.48) | 47 (1 RCT) | ⊕⊕⊝⊝ LOW 1 | |
| Improvement in functional ability | ‐ | ‐ | ‐ | ‐ | ‐ | Not reported |
| Quality of life | ‐ | ‐ | ‐ | ‐ | ‐ | Not reported |
| Adverse events. Follow‐up to 4 months |
In the injection group only, there were 2/22 (9%) cases of transient ptosis and 4/22 (18%) with transient vertical deviation, with a total complication rate of 24% per injection and 27% per participant. All adverse events recovered within the follow‐up time period of 6 months with no lasting adverse effects. | 47 (1 RCT) |
⊕⊕⊝⊝ LOW 1 | |||
| *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; 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 | ||||||
1 Downgraded one level for risk of bias (investigators were aware of the randomisation and it was not possible to mask investigators or participants to the allocation and there was variable follow‐up between groups) and downgraded one level for imprecision (confidence intervals include 1, no effect).