Characteristics | Categories | Trials with treatment effect estimate and/or p-value reported (N = 1400) | Trials with no treatment effect estimate or p-value reported (N = 1423) |
---|---|---|---|
Phase of the study | Phase 3 | 948 (68) | 728 (51) |
Phase 4 | 452 (32) | 695 (49) | |
Intervention type | Drug | 1088 (78) | 1014 (71) |
Mixed interventions | 180 (13) | 148 (10) | |
Biological | 48 (3) | 96 (7) | |
Device | 40 (3) | 97 (7) | |
Other | 44 (3) | 68 (5) | |
Control group | Placebo or no treatment | 822 (59) | 516 (36) |
Active treatment | 578 (41) | 907 (64) | |
Sponsorship | Industry totally or partly | 1162 (83) | 1055 (74) |
Academic only | 238 (17) | 368 (26) | |
Countries | Single country | 646 (46) | 982 (69) |
Multiple countries | 568 (41) | 292 (21) | |
Not reported | 186 (13) | 149 (10) | |
Location | At least one site in the USA | 846 (61) | 822 (58) |
No site in the USA | 368 (26) | 452 (32) | |
Not reported | 186 (13) | 149 (10) | |
Subject to the FDAAA | Yes | 951 (68) | 843 (59) |
No | 377 (27) | 556 (39) | |
Not reported | 72 (5) | 24 (2) | |
Centers | Multicenter | 929 (66) | 696 (49) |
Single center | 285 (20) | 578 (41) | |
Not reported | 186 (13) | 149 (10) | |
Sample size | Median (Q1-Q3) | 270 (116–520) | 156 (60–378) |
Time to results first received at ClinicalTrials.gov (month) | Median (Q1-Q3) | 13.5 (11.7–26.4) | 17.1 (12.0–32.3) |