Early Discontinuation, Results Reporting, and Publication of Gynecology Clinical Trials From 2007 to 2020

Underrepresentation of racial and ethnic minority groups in gynecologic oncology: An analysis of over 250 trials

OBJECTIVE

To describe the participation of racial and ethnic minority groups (REMGs) in gynecologic oncology trials.

METHODS

Gynecologic oncology studies registered on ClinicalTrials.gov between 2007 and 2020 were identified. Trials with published results were analyzed based on reporting of race/ethnicity in relation to disease site and trial characteristics. Expected enrollment by race/ethnicity was calculated and compared to actual enrollment, adjusted for 2010 US Census population data.

RESULTS

2146 gynecologic oncology trials were identified. Of published trials (n = 252), 99 (39.3%) reported race/ethnicity data. Recent trials were more likely to report these data (36% from 2007 to 2009; 51% 2013-2015; and 53% from 2016 to 2018, p = 0.01). Of all trials, ovarian cancer trials were least likely to report race/ethnicity data (32.1% vs 39.3%, p = 0.011). Population-adjusted under-enrollment for Blacks was 7-fold in ovarian cancer, Latinx 10-fold for ovarian and 6-fold in uterine cancer trials, Asians 2.5-fold in uterine cancer trials, and American Indian and Alaska Native individuals 6-fold in ovarian trials. Trials for most disease sites have enrolled more REMGs in recent years - REMGs made up 19.6% of trial participants in 2007-2009 compared to 38.1% in 2016-2018 (p < 0.0001).

CONCLUSION

Less than half of trials that published results reported race/ethnicity data. Available data reveals that enrollment of REMGs is significantly below expected rates based on national census data. These disparities persisted even after additionally adjusting for population size. Despite improvement in recent years, additional recruitment of REMGs is needed to achieve more representative and equitable participation in gynecologic cancer clinical trials.

The international clinical trials registry platform (ICTRP): data integrity and the trends in clinical trials, diseases, and drugs

Introduction: Clinical trials are the gold standard for testing new therapies. Databases like ClinicalTrials.gov provide access to trial information, mainly covering the US and Europe. In 2006, WHO introduced the global ICTRP, aggregating data from ClinicalTrials.gov and 17 other national registers, making it the largest clinical trial platform by June 2019. This study conducts a comprehensive global analysis of the ICTRP database and provides framework for large-scale data analysis, data preparation, curation, and filtering. Materials and methods: The trends in 689,793 records from the ICTRP database (covering trials registered from 1990 to 2020) were analyzed. Records were adjusted for duplicates and mapping of agents to drug classes was performed. Several databases, including DrugBank, MESH, and the NIH Drug Information Portal were used to investigate trends in agent classes. Results: Our novel approach unveiled that 0.5% of the trials we identified were hidden duplicates, primarily originating from the EUCTR database, which accounted for 82.9% of these duplicates. However, the overall number of hidden duplicates within the ICTRP seems to be decreasing. In total, 689 793 trials (478 345 interventional) were registered in the ICTRP between 1990 and 2020, surpassing the count of trials in ClinicalTrials.gov (362 500 trials by the end of 2020). We identified 4 865 unique agents in trials with DrugBank, whereas 2 633 agents were identified with NIH Drug Information Portal data. After the ClinicalTrials.gov, EUCTR had the most trials in the ICTRP, followed by CTRI, IRCT, CHiCTR, and ISRCTN. CHiCTR displayed a significant surge in trial registration around 2015, while CTRI experienced rapid growth starting in 2016. Conclusion: This study highlights both the strengths and weaknesses of using the ICTRP as a data source for analyzing trends in clinical trials, and emphasizes the value of utilizing multiple registries for a comprehensive analysis.

Race and Ethnicity Reporting and Representation in Obstetrics and Gynecology Clinical Trials and Publications From 2007-2020

Importance

Clinical trials guide evidence-based obstetrics and gynecology (OB-GYN) but often enroll nonrepresentative participants.

Objective

To characterize race and ethnicity reporting and representation in US OB-GYN clinical trials and their subsequent publications and to analyze the association of subspecialty and funding with diverse representation.

Design and Setting

Cross-sectional analysis of all OB-GYN studies registered on ClinicalTrials.gov (2007-2020) and publications from PubMed and Google Scholar (2007-2021). Analyses included logistic regression controlling for year, subspecialty, phase, funding, and site number. Data from 332 417 studies were downloaded. Studies with a noninterventional design, with a registration date before October 1, 2007, without relevance to OB-GYN, with no reported results, and with no US-based study site were excluded.

Exposures

OB-GYN subspecialty and funder.

Main Outcomes and Measures

Reporting of race and ethnicity data and racial and ethnic representation (the proportion of enrollees of American Indian or Alaskan Native, Asian, Black, Latinx, or White identity and odds of representation above US Census estimates by race and ethnicity).

Results

Among trials with ClinicalTrials.gov results (1287 trials with 591 196 participants) and publications (1147 trials with 821 111 participants), 662 (50.9%) and 856 (74.6%) reported race and ethnicity data, respectively. Among publications, gynecology studies were significantly less likely to report race and ethnicity than obstetrics (adjusted odds ratio [aOR], 0.54; 95% CI, 0.38-0.75). Reproductive endocrinology and infertility trials had the lowest odds of reporting race and ethnicity (aOR, 0.14; 95% CI, 0.07-0.27; reference category, obstetrics). Obstetrics and family planning demonstrated the most diverse clinical trial cohorts. Compared with obstetric trials, gynecologic oncology had the lowest odds of Black representation (ClinicalTrials.gov: aOR, 0.04; 95% CI, 0.02-0.09; publications: aOR, 0.06; 95% CI, 0.03-0.11) and Latinx representation (ClinicalTrials.gov: aOR, 0.05; 95% CI, 0.02-0.14; publications: aOR, 0.23; 95% CI, 0.10-0.48), followed by urogynecology and reproductive endocrinology and infertility. Urogynecology (ClinicalTrials.gov: aOR, 0.15; 95% CI, 0.05-0.39; publications: aOR, 0.24; 95% CI, 0.09-0.58) had the lowest odds of Asian representation.

Conclusions and Relevance

Race and ethnicity reporting and representation in OB-GYN trials are suboptimal. Obstetrics and family planning trials demonstrate improved representation is achievable. Nonetheless, all subspecialties should strive for more equitably representative research.

How many US obstetrical trials reach publication? A cross-sectional analysis of ClinicalTrials.gov and PubMed from 2007 to 2019

BACKGROUND

Obstetrical clinical trials are the foundation of evidence-based medicine during pregnancy. As more obstetrical trials are conducted, understanding the publication characteristics of these trials is of utmost importance to advance obstetrical health.

OBJECTIVE

This study aimed to characterize the frequency of publication and trial characteristics associated with publication among obstetrical clinical trials in the United States. We additionally sought to examine time from trial completion to publication.

STUDY DESIGN

This was a cross-sectional analysis of completed obstetrical trials with an intervention design and at least 1 site in the United States registered to ClinicalTrials.gov from 2007 to 2019. Trial characteristics were cross-referenced with PubMed to determine publication status up to 2021 using the National Clinical Trial identification number. Bivariable analyses were conducted to determine trial characteristics associated with publication. Multivariable logistic regression models controlling for prespecified covariates were generated to estimate the relationship between funding, primary purpose, and therapeutic foci with publication. Additional exploratory analyses of other trial characteristics were conducted. Time to publication was analyzed using Kaplan-Meier curves and Cox regression models.

RESULTS

Of the 1879 obstetrical trials with registered completion, a total of 575 (30.6%) had at least 1 site in the United States, were completed before October 1, 2019, and were included in this analysis. Between October 2007 and October 2019, fewer than two-thirds (N=348, 60.5%) of trials reached publication. Annual rates of publication ranged from 46.4% in 2018 to 70.0% in 2007. No difference was observed in publication by funding, primary purpose, or therapeutic foci (all P>.05). Trials with characteristics indicating high trial quality-including randomized allocation scheme, ≥50 participants enrolled, ≥2 sites, and presence of a data safety monitoring committee-had increased odds of publication compared with those without such characteristics (all P<.05). For example, studies with randomized allocation of intervention had 2-fold greater odds of publication than nonrandomized studies (adjusted odds ratio, 2.09; 95% confidence interval, 1.30-3.37). Studies with ≥150 participants had nearly 8-fold odds of publication (adjusted odds ratio, 7.90; 95% confidence interval, 3.78-17.49) relative to studies with <50 participants. Temporal analysis demonstrated variability in time to publication among obstetrical trials, with a median time of 20.1 months after trial completion, and with most trials that reached publication having been published by 40 months. No difference was observed in time to publication by funding, primary purpose, or therapeutic foci (all P>.05).

CONCLUSION

Publication of obstetrical trials remains suboptimal, with significant differences observed between trials with indicators of high quality and those without. Most trials that reach publication are published within 2 years of registered completion on ClinicalTrials.gov.