Associations between prospective registration and other variables
| Variable (yes/no) | n (%) prospectively registered | P value (χ2) | |
| ICMJE member journal | Y | 28 (63.6%) | p=0.10 |
| N | 943 (50.1%) | ||
| ICMJE member/following journal | Y | 329 (49.2%) | p=0.47 |
| N | 642 (51.0%) | ||
| TRN reporting in abstract | Y | 404 (55.4%) | p=0.0007 |
| N | 567 (47.3%) | ||
| Industry sponsorship | Y | 163 (59.3%) | p=0.002 |
| N | 808 (48.9%) |
ICMJE, International Committee of Medical Journal Editors; TRN, trial registration number.