Grading of Recommendation, Assessment, Development and Evaluation (GRADE) evidence profile
| Outcome | Measure | n (N) | Effect estimates | Certainty | Benefit | |||||
| Risk of bias | Inconsistency | Indirectness | Imprecision | Other | Overall certainty | |||||
| Treatment success | N | 4 (383) | Relative risk 1.37 (1.08–1.73), I2=63% | Serious# | Not serious | Not serious | Not serious | Not serious | Moderate | Yes |
| Overall symptom score | Post-treatment scores | 3 (316) | SMD 0.86 (0.63–1.09), I2=0% | Serious# | Not serious | Not serious | Not serious | Not serious | Moderate | Yes |
| Change from pre-treatment | 1 (50) | SMD 0.80 (0.22–1.38) | Serious# | Not serious | Not serious | Not serious | Not serious | |||
| N with improvement | 1 (200) | Relative risk 1.18 (1.07–1.31) | Serious# | Not serious | Not serious | Not serious | Not serious | |||
| Dyspnoea cough attacks | 1 (30) | MD −1.40 (−3.51–0.71) | Serious# | Not serious | Not serious | Serious¶ | Not serious | |||
| Breathlessness | N with absence | 2 (276) | Relative risk 1.36 (0.55–3.38), I2=85% | Serious# | Serious+ | Not serious | Serious¶ | Not serious | Very low | No |
| Change from pre-treatment in Borg's scale | 1 (59) | MD 0.40 (−0.55–1.35) | Serious# | Not serious | Not serious | Serious¶ | Not serious | |||
| N with improvement | 1 (27) | Relative risk 1.08 (0.69–1.68) | Serious# | Not serious | Not serious | Serious¶ | Not serious | |||
| N with dyspnoea at rest | 1 (40) | Relative risk 0.18 (0.01–3.56) | Serious# | Not serious | Not serious | Serious¶ | Not serious | |||
| Cough | N with absence | 2 (276) | Relative risk 1.93 (1.15–3.23), I2=29% | Serious# | Not serious | Not serious | Not serious | Not serious | Moderate | Yes |
| N with improvement in frequency/in intensity | 1 (122) | Relative risk 1.40 (0.88–2.22)/Relative risk 2.06 (1.23–3.43) | Serious# | Not serious | Not serious | Serious¶ | Not serious | |||
| Ease of expectoration | N with improvement | 2 (149) | Relative risk 2.94 (1.68–5.12), I2=0% | Serious# | Not serious | Not serious | Not serious | Not serious | Moderate | Yes |
| N with absence | 1 (226) | Relative risk 3.71 (1.87–7.38) | Serious# | Not serious | Not serious | Not serious | Not serious | |||
| Health-related quality of life | Change from pre-treatment | 1 (78) | MD 0.7 (0.6–0.8) | Serious# | Not serious | Not serious | Serious¶ | Not serious | Low | Yes |
| Length of hospital stay | Mean duration in days | 3 (114) | MD −1.04 (−4.66–2.58), I2=76% | Serious# | Not serious | Not serious | Serious¶ | Not serious | Low | No |
| ICU admission and ventilation | N | 2 (83) | Relative risk 0.36 (0.06–2.17), I2=0% | Serious# | Not serious | Not serious | Serious¶ | Not serious | Low | No |
| Future exacerbations | N with re-exacerbation at day 30 | 2 (55) | Relative risk 0.08 (0.00–1.28) | Serious# | Not serious | Not serious | Serious¶ | Not serious | Very Low | Yes |
| HR, 2 months follow-up | 1 (40) | HR 0.169 (0.033–0.875) | Serious# | Not serious | Not serious | Serious¶ | Not serious | |||
| Time to first (days), 6 months follow-up | 1 (38) | MD 27.70 (−4.55–59.95) | Serious# | Not serious | Not serious | Serious¶ | Not serious | |||
| Mortality | N | 4 (173) | Relative risk 0.73 (0.11–4.90), I2=16% | Serious# | Not serious | Not serious | Serious¶ | Not serious | Low | No |
| SAEs | N | 2 (109) | No SAEs were observed | Serious# | Not serious | Not serious | Serious¶ | Not serious | Low | No risk |
#All studies included in this systematic review were deemed to be of at least some concern of methodological bias. ¶Broad confidence intervals and/or insufficient overall study population. +Marchioni et al. [31] reported significant improvement in dyspnoea; however, significance was lost in a meta-analysis that included a second, smaller randomised controlled trial. n: Number of trials; N: number of patients; HR: hazard ratio; ICU: intensive care unit; MD: mean difference; SAE: serious adverse event; SMD: standardised mean difference.