Table 2.
Associations between trail features and early discontinuation in obstetrical clinical trials
| Trial feature | Hazard ratio (95% confidence interval) | P value |
|---|---|---|
| All trials | ||
| Nonobstetrical | Reference | |
| Obstetrical | 1.40 (1.21–1.62) | <.0001 |
| Obstetrical trials only | ||
| Fundinga | ||
| Industry | Reference | |
| Academic | 1.04 (0.62–1.74) | .88 |
| United States government | 0.23 (0.07–0.69) | .009 |
| Primary purpose | ||
| Treatment | Reference | |
| Basic science | 0.58 (0.17–1.99) | .38 |
| Prevention | 0.95 (0.64–1.42) | .82 |
| Otherb | 1.33 (0.87–2.03) | .19 |
| Phase | ||
| Phase 2/3–3 | Reference | |
| Not Applicablec | 0.54 (0.34–0.86) | .009 |
| Phase 1 | 0.52 (0.25–1.09) | .08 |
| Phase 1/2–2 | 0.64 (0.33–1.23) | .18 |
| Phase 4 | 1.17 (0.67–2.04) | .15 |
| Enrollmentd | ||
| 100–499 | Reference | |
| 0–9 | 49.82 (30.10–82.47) | <.0001 |
| 10–49 | 6.29 (4.10–9.64) | <.0001 |
| 50–99 | 2.01 (1.20–3.36) | .007 |
| 500–999 | 0.72 (0.25–2.02) | .53 |
| >999 | 0.79 (0.37–1.65) | .53 |
| Blinding | ||
| None | Reference | |
| Single | 0.62 (0.40–0.96) | .03 |
| Double | 0.83 (0.54–1.26) | .37 |
| Randomization | ||
| Nonrandomized | Reference | |
| Randomized | 2.00 (1.28–3.13) | .002 |
| Oversight by a data safety monitoring committee | ||
| No | Reference | |
| Yes | 1.12 (0.82–1.54) | .47 |
| Location | ||
| Low- and middle-income country only | Reference | |
| High-income country | 1.83 (1.05–3.21) | .03 |
| Number of facilities | ||
| 1 | Reference | |
| >2 | 1.35 (0.92–1.98) | .13 |
| Therapeutic focuse | ||
| All other trials | Reference | |
| Cesarean delivery | 1.72 (1.03–2.87) | .04 |
| Nutrition | 1.04 (0.63–1.73) | .87 |
| Anesthesia | 1.86 (1.12–3.10) | .02 |
| Infection | 1.57 (0.95–2.62) | .08 |
| Fetal | 0.95 (0.59–1.51) | .81 |
| Mental health | 0.94 (0.52–1.70) | .84 |
| Early delivery | 1.08 (0.67–1.74) | .75 |
| Diabetes mellitus | 0.59 (0.33–1.06) | .08 |
Steinberg et al. The obstetrical clinical trial landscape. AJOG MFM 2021.
Funding categories were determined with data on the sponsor and collaborators. Industry funding includes trials with an industry sponsor or collaborating agency. United States government trials include remaining trials with a United States government sponsor or collaborating agency. Academic trials include all other trials
Other primary purposes include diagnostic, screening, supportive care, health services research, and other
On ClinicalTrials.gov, “Not Applicable” is used to describe trials without Food and Drug Administration–defined phases, including trials of devices or behavioral interventions
Enrollment included both actual enrollment (for completed trials) and anticipated enrollment (for ongoing trials with continued enrollment)
Trials could have >1 therapeutic focus. For analysis, each therapeutic focus was treated as a binary variable.