Table 2 Characteristics of included trials by blinding status of the statistician
Characteristic | Statistician blinded prior to the final analysis | Â | ||
|---|---|---|---|---|
No (N = 83) | Yes (N = 69) | Unknown (N = 27) | Total (N = 179) | |
Publication year, n (%) | ||||
 2016 | 20 (56%) | 12 (33%) | 4 (11%) | 36 |
 2017 | 12 (43%) | 11 (39%) | 5 (18%) | 28 |
 2018 | 22 (58%) | 13 (34%) | 3 (8%) | 38 |
 2019 | 17 (44%) | 15 (38%) | 7 (18%) | 39 |
 2020 | 12 (32%) | 18 (47%) | 8 (21%) | 38 |
Journal, n (%) | ||||
 HTA | 64 (44%) | 59 (41%) | 22 (15%) | 145 |
 EME | 19 (56%) | 10 (29%) | 5 (15%) | 34 |
Trial design, n (%) | ||||
 Individually randomised | 72 (46%) | 60 (38%) | 24 (15%) | 156 |
 Cluster | 8 (50%) | 7 (44%) | 1 (6%) | 16 |
 Factorial | 1 (25%) | 2 (50%) | 1 (25%) | 4 |
 Other | 2 (67%) | 0 (0%) | 1 (33%) | 3 |
Interventions, n (%) | ||||
 Drug | 36 (49%) | 25 (34%) | 12 (16%) | 73 |
 Device | 4 (44%) | 2 (22%) | 3 (33%) | 9 |
 Surgery | 11 (69%) | 1 (6%) | 4 (25%) | 16 |
 Complex | 34 (38%) | 45 (51%) | 10 (11%) | 89 |
CTIMP, n (%) | ||||
 No | 48 (44%) | 46 (42%) | 15 (14%) | 109 |
 Yes | 35 (50%) | 23 (33%) | 12 (17%) | 70 |
Hypothesis testing framework, n (%) | ||||
 Superiority | 75 (46%) | 66 (40%) | 22 (13%) | 163 |
 Non-inferiority | 8 (57%) | 2 (14%) | 4 (29%) | 14 |
 Equivalence | 0 (0%) | 1 (50%) | 1 (50%) | 2 |
Treatment groups, n (%) | ||||
 2 | 69 (48%) | 54 (37%) | 22 (15%) | 145 |
 >2 | 14 (41%) | 15 (44%) | 5 (15%) | 34 |
Placebo controlled, n (%) | ||||
 No | 60 (45%) | 52 (39%) | 20 (15%) | 132 |
 Yes | 23 (49%) | 17 (36%) | 7 (15%) | 47 |
Multiple primary outcomes, n (%) | ||||
 No | 64 (44%) | 60 (41%) | 21 (14%) | 145 |
 Yes | 19 (56%) | 9 (26%) | 6 (18%) | 34 |
Clinical area, n (%) | ||||
 Blood | 2 (67%) | 0 (0%) | 1 (33%) | 3 |
 Cancer | 7 (64%) | 2 (18%) | 2 (18%) | 11 |
 Cardiovascular | 5 (42%) | 5 (42%) | 2 (17%) | 12 |
 Generic health relevance | 5 (36%) | 6 (43%) | 3 (21%) | 14 |
 Infection | 12 (71%) | 2 (12%) | 3 (18%) | 17 |
 Inflammatory and immune system | 2 (50%) | 2 (50%) | 0 (0%) | 4 |
 Injuries and accidents | 5 (63%) | 2 (25%) | 1 (13%) | 8 |
 Mental health | 6 (25%) | 13 (54%) | 5 (21%) | 24 |
 Metabolic and endocrine | 5 (71%) | 1 (14%) | 1 (14%) | 7 |
 Musculoskeletal | 2 (67%) | 1 (33%) | 0 (0%) | 3 |
 Neurological | 6 (40%) | 5 (33%) | 4 (27%) | 15 |
 Oral and gastrointestinal | 3 (43%) | 2 (29%) | 2 (29%) | 7 |
 Renal and urogenital | 3 (50%) | 2 (33%) | 1 (17%) | 6 |
 Reproductive health and childbirth | 8 (50%) | 7 (44%) | 1 (6%) | 16 |
 Respiratory | 5 (50%) | 5 (50%) | 0 (0%) | 10 |
 Skin | 2 (29%) | 5 (71%) | 0 (0%) | 7 |
 Stroke | 4 (33%) | 7 (58%) | 1 (8%) | 12 |
 Other | 1 (33%) | 2 (67%) | 0 (0%) | 3 |