Baseline characteristics of the patients in the included trials
| Study | Interventions | Age (years) (mean (SD)) | Baseline EDSS (mean (SD)) | Disease duration (years) (mean (SD)) | Pre-study change in EDSS (mean (SD)) | Pre-study duration of progression (years) (mean (SD)) | No of pre-study relapses (mean (SD)) | Percentage of patients without pre-study relapse |
| European SG18 | IFNβ-1b 250 μg | 41.1 (7.2) | 5.1 (1.1) | 12.8 (6.6) | 1.5 (NR) | 3.8 (2.7) | 1.7 (0.85) | 32 |
| Placebo | 40.9 (7.2) | 5.2 (1.1) | 13.4 (7.5) | 3.8 (3.4) | 28 | |||
| SPECTRIMS19 | IFNβ-1a 22 μg | 42.6 (7.3) | 5.3 (1.1) | 12.9 (6.9) | 1.5 (0.8) | 3.7 (2.7) | 0.9 (1.3) | 52 |
| IFNβ-1a 44 μg | 43.1 (7.2) | 5.5 (1.1) | 13.3 (7.4) | 1.6 (0.9) | 4.2 (3.1) | 0.9 (1.4) | 54 | |
| Placebo | 42.7 (6.8) | 5.4 (1.1) | 13.7 (7.2) | 1.7 (1.0) | 4.1 (3.2) | 0.9 (1.2) | 52 | |
| IMPACT20 | IFNβ-1a 60 μg | 47.2 (8.2) | 5.2 (1.1) | 16.2 (9.0) | NR | NR | 0.6 (1.1) | 37 |
| Placebo | 47.9 (7.7) | 5.2 (1.1) | 16.7 (9.0) | NR | NR | 0.5 (0.9) | 44 | |
| Nordic21 | IFNβ-1a 22 μg | 45.1 (NR) | 4.7 (NR) | 14.2 (NR) | NR | 4.8 (NR) | 1.7 (0.4) | 40 |
| Placebo | 46.4 (NR) | 5.0 (NR) | 14.4 (NR) | NR | 6.1 (NR) | 1.6 (0.4) | 34 | |
| North American SG22 | IFNβ-1b 250 μg | 46.1 (8.0) | 5.2 (1.1) | 14.6 (7.8) | 1.7 (0.9) | 4.0 (3.3) | 0.8 (1.1) | 54 |
| IFNβ-1b 160 μg | 46.8 (8.3) | 5.1 (1.2) | 14.5 (8.7) | 1.7 (0.9) | 4.1 (3.5) | 0.9 (1.6) | 55 | |
| Placebo | 47.6 (8.2) | 5.1 (1.1) | 14.9 (8.3) | 1.7 (0.9) | 4.1 (3.5) | 0.8 (1.2) | 56 |
EDSS, Expanded Disability Status Scale; IFNβ, interferon β; NR, not reported.