Interventional | Observational | Overall | |
Number of studies | 430 | 84 | 514 |
Operational | |||
Status | |||
Ongoing | 134 (31%) | 28 (33%) | 162 (32%) |
Closed | 227 (53%) | 49 (58%) | 276 (54%) |
Not yet recruiting | 21 (5%) | 2 (2%) | 23 (5%) |
Withdrawn | 11 (3%) | 1 (1%) | 12 (2%) |
Unknown status | 37 (9%) | 4 (5%) | 41 (8%) |
Sponsor | |||
Academic | 339 (79%) | 69 (82%) | 408 (79%) |
Industry | 91 (21%) | 15 (18%) | 106 (21%) |
Location | |||
North America | 248 (58%) | 44 (53%) | 292 (57%) |
Europe | 97 (23%) | 29 (35%) | 126 (25%) |
Asia | 46 (11%) | 6 (7%) | 52 (10%) |
Intercontinental | 20 (5%) | 4 (5%) | 24 (5%) |
Other | 14 (3%) | 1 (1%) | 15 (3%) |
Unknown | 5 (1%) | – | 5 (1%) |
Number of centres | |||
Monocentric | 257 (60%) | 49 (58%) | 306 (60%) |
Multicentric national | 119 (28%) | 21 (25%) | 140 (27%) |
Multicentric international | 24 (6%) | 9 (11%) | 33 (6%) |
Unknown | 30 (7%) | 5 (6%) | 35 (7%) |
Dissemination | |||
Published results among closed studies* (n=276) | |||
Has results on clinicaltrials.gov | 49 (22%) | 2 (4%) | 51 (18%) |
Publication on PubMed | 40 (18%) | 5 (10%) | 45 (16%) |
Design | |||
Blinded | |||
No | 286 (67%) | – | 286 (56%) |
Yes | 144 (33%) | – | 144 (28%) |
Not applicable | – | 84 (100%) | 84 (16%) |
Study arms | |||
Single arm | 136 (32%) | 67 (80%) | 203 (39%) |
Multiarm | 294 (68%) | 17 (20%) | 311 (61%) |
Randomisation | |||
No | 152 (35%) | – | 152 (30%) |
Yes | 278 (65%) | – | 278 (54%) |
Not applicable | – | 84 (100%) | 84 (16%) |
Number of primary outcomes | |||
1 | 337 (78%) | 65 (77%) | 402 (78%) |
2 | 38 (9%) | 5 (6%) | 43 (8%) |
≥3 | 42 (10%) | 8 (10%) | 50 (10%) |
Unknown | 13 (3%) | 6 (7%) | 19 (4%) |
Actual sample size among closed studies (n=276) | |||
Median | 60 | 74 | 60 |
IQR | 21–150 | 38–255 | 23–177 |
Number of studies | 221 | 49 | 270 |
Planned sample size among non-closed studies (n=238) | |||
Median | 72 | 230 | 80 |
IQR | 30–176 | 50–500 | 38–200 |
Number of studies | 202 | 35 | 237 |
*On clinicaltrials.gov, all trials with results were closed trials; nevertheless, we found additional publications on PubMed for 15 interventional not closed studies (seven ongoing trials, one not yet recruiting, two withdrawn and five unknown status)