| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
|---|---|---|---|---|---|---|
| Assumed risk | Corresponding risk | |||||
| Tiotropium | LABA plus tiotropium | |||||
|
Change in quality of life St George’s Respiratory Questionaire (SGRQ). Scale from: 0 to 100. Follow-up: 6 to 12 months |
The mean change in quality of life in the control group was −4.5 units1 |
The mean change in quality of life in the intervention group was −6.3 units1 (−7.43 to −4.79) |
MD −1.61 (−2.93 to −0.29) |
732 (2 studies) |
⊕⊕⊕○ moderate2 |
The mean treatment effect was statistically significant but it was smaller than what is regarded as a clinically important difference |
|
Exacerbations leading to hospital admission Number of patients experiencing one or more events Follow-up: 6 to 12 months |
88 per 1000 |
93 per 1000 (57 to 148) |
OR 1.07 (0.63 to 1.81) |
732 (2 studies) |
⊕⊕○○ low2,3 |
|
|
Hospital admission (all cause) Number of patients experiencing one or more events Follow-up: 6 to 12 months |
119 per 1000 |
120 per 1000 (79 to 179) |
OR 1.01 (0.63 to 1.61) |
732 (2 studies) |
⊕⊕○○ low2,3 |
|
|
Mortality (all cause) Number of patients Follow-up: 3 to 12 months |
4 per 1000 |
6 per 1000 (2 to 16) |
OR 1.56 (0.56 to 4.33) |
3263 (5 studies) |
⊕⊕○○ low4 |
|
The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (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; OR: Odds ratio;
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 impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact 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.
The control group risk is based on Aaron 2007.
One study was a year long with high and unbalanced dropouts.
Wide confidence interval and few participants and events.
There were two trials with no deaths and few deaths in the remaining three trials, leading to a wide confidence interval. Mortality was largely unknown in those WHO discontinued treatment.