Table 1.
Summary data and sensitivity analyses for placebo controlled trials
| Number of | Success/total | |||||
| Trial characteristic | Trials | Patients | Treatment | Placebo | RB (95% CI) | NNT (95% CI) |
| All trials | 14 | 1502 | 371/771 | 193/731 | 1.9 (1.7 to 2.2) | 4.6 (3.8 to 5.9) |
| Quality and validity | ||||||
| Quality score 3 to 5 | 11 | 1312 | 294/678 | 144/634 | 2.0 (1.7 to 2.4) | 4.8 (3.9 to 6.4) |
| Quality score 2 | 3 | 190 | 77/93 | 49/97 | 1.6 (1.3 to 2.0) | 3.1 (2.2 to 5.1) |
| Validity score ≥ 9 and quality score ≥ 3 | 10 | 1197 | 247/622 | 98/575 | 2.4 (2.0 to 3.0) | 4.4 (3.6 to 5.6) |
| Trial group size | ||||||
| ≤ 50 patients | 6 | 343 | 95/172 | 54/171 | 1.8 (1.4 to 2.3) | 4.2 (3.0 to 7.4) |
| > 50 patients | 8 | 1159 | 276/599 | 139/560 | 2.0 (1.7 to 2.3) | 4.7 (3.8 to 6.3) |
| Outcome type | ||||||
| preferred outcomes | 8 | 920 | 198/462 | 85/458 | 2.3 (1.9 to 2.9) | 4.1 (3.3 to 5.4) |
| lower preference outcomes | 6 | 582 | 173/309 | 108/273 | 1.6 (1.4 to 1.9) | 6.1 (4.1 to 12) |
| Condition | ||||||
| knee osteoarthritis | 5 | 567 | 127/307 | 58/260 | 2.0 (1.6 to 2.6) | 5.3 (3.8 to 8.6) |
| other musculoskeletal | 9 | 935 | 244/464 | 135/471 | 1.9 (1.6 to 2.2) | 4.2 (3.3 to 5.6) |