Summary of findings 3. Respiratory muscle training versus no training in DMD.
| Respiratory muscle training compared to no training in DMD | ||||||
| Patient or population: children and young males with DMD Intervention: respiratory muscle training Comparison: no training | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk or value with no training | Risk or value with respiratory muscle training | |||||
| Measures of lung capacity over the short term (less than 3 months) | ‐ | Three cross‐over trials measured short‐term outcomes but did not provide data for each study period. | ||||
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Measures of lung capacity over the medium term (greater than 3 months but less than 1 year) Measured by: post‐intervention % predicted VC Follow‐up: 6 months |
The mean post‐intervention % predicted VC was 44.4% | The mean post‐intervention % predicted VC was 3.50% higher than in the no training group (14.35% lower to 21.35% higher) | ‐ | 30 (1 RCT) | ⊕⊕⊝⊝ Lowa | There may be no clear difference in % predicted VC with RMT in comparison to no training. For more lung capacity outcomes, see text. |
| Measures of lung capacity over the long term (greater than 1 year) | ‐ | Not measured | ||||
| Physical function in carrying out activities of daily living | ‐ | Not measured | ||||
| Quality of life | ‐ | Not measured | ||||
| Number of unscheduled hospitalizations for episodes of chest infection or acute exacerbation of chronic respiratory failure within 1 year of randomization | ‐ | Not measured | ||||
| All adverse events | ‐ | Not measured | ||||
| *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; DMD: Duchenne muscular dystrophy; MD: mean difference; RCT: randomized controlled trial; VC: vital capacity | ||||||
| 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. | ||||||
aWe downgraded the evidence twice for serious imprecision due to small sample size and the CIs included both an important effect and no effect.