Table 2.
Methodological quality of included trials
| Trials
|
Randomisation*
|
Blinding†
|
Withdrawals or dropouts‡
|
Jadad's quality score10
|
Methods confirmed
|
Withdrawals (%)
|
|
|---|---|---|---|---|---|---|---|
| Intervention group | Control group | ||||||
| Anti-leukotrienes versus placebo as add-on therapy to inhaled glucocorticoids | |||||||
| Laviolette et al9 | 2 | 2 | 1 | 5 | Yes | 8 | 11 |
| Simons et al14 | 2 | 2 | 0 | 4 | Yes | 3 | 2 |
| Tamaoki et al7 | 1 | 2 | 1 | 4 | No | 2 | 8 |
| Tomita et al18 | 1 | 0 | 0 | 1 | No | Not reported | Not reported |
| Virchow et al8 | 2 | 2 | 1 | 5 | Yes | 18 | 18 |
| Wada et al15 | 1 | 0 | 1 | 2 | No | 8 | 18 |
| Anti-leukotrienes as add-on therapy to inhaled glucocorticoids versus double dose of inhaled glucocorticoids | |||||||
| Nayak et al17 | 2 | 2 | 1 | 5 | Yes | 14 | 16 |
| Ringdal et al16 | 2 | 2 | 1 | 5 | Yes | 11 | 6 |
| Anti-leukotrienes versus placebo as add-on therapy to tapering doses of inhaled glucocorticoids | |||||||
| Baba et al21 | 1 | 0 | 0 | 1 | No | Not reported | Not reported |
| Bateman et al19 | 2 | 2 | 1 | 5 | Yes | 20 | 22 |
| Laitinen et al20 | 2 | 2 | 1 | 5 | Yes | 15 | 14 |
| Lofdahl et al6 | 2 | 2 | 1 | 5 | Yes | 15 | 27 |
| Shingo et al22 | 2 | 2 | 1 | 5 | Yes | 10 | 8 |
*
2=randomised, appropriate method; 1=randomised, method not described; 0=not randomised.†2=double blind, blinding appropriate; 1=double blind, blinding not reported; 0=no blinding.‡1=described by group; 0=not described by group.