Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Beth Israel Deaconess Medical Center, Boston, MA (Drs Gupta and Wagner); Department of Obstetrics, Gynecology, and Reproductive Biology, Harvard Medical School, Boston, MA (Drs Gupta and Wagner).
Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA (Dr Oliver).
Am J Obstet Gynecol MFM. 2023 Sep;5(9):101066. doi: 10.1016/j.ajogmf.2023.101066. Epub 2023 Jul 5.
A portion of obstetrical randomized clinical trials registered on ClinicalTrials.gov are not published in peer-reviewed journals.
This study aimed to compare the characteristics of completed published vs unpublished randomized clinical trials in obstetrics registered on ClinicalTrials.gov and to identify barriers to publication.
This cross-sectional study queried ClinicalTrials.gov for all completed obstetrical randomized clinical trials registered between January 1, 2009, and December 31, 2018. For each completed obstetrical randomized clinical trial, we abstracted the following registration fields from ClinicalTrials.gov: ClinicalTrials.gov identifier, recruitment status, trial start and completion dates, study results, type of intervention, study phase, enrollment size, funder type, location, and facilities. Calculated variables included time to completion. In May 2021, we used PubMed and Google Scholar to identify the publication status of completed trials, and we compared the characteristics of published vs unpublished randomized clinical trials. The corresponding authors' e-mail addresses for the unpublished studies were collected from ClinicalTrials.gov and departmental websites. Between September 2021 and March 2022, the authors of these completed but unpublished obstetrical randomized clinical trials were contacted and invited to respond to a survey examining perceptions of barriers to publication, responses of which were collected and presented as counts and percentages.
Of the 647 obstetrical randomized clinical trials marked as completed on ClinicalTrials.gov, 378 (58%) were published, and 269 (42%) were unpublished. Unpublished trials were more likely to have an enrollment size of <50 participants (14.5% published vs 25.3% unpublished; P<.001) and less likely to be conducted at multiple sites (25.4% published vs 17.5% unpublished; P<.02). The main barriers to publication reported in the survey by authors whose trials were not published included lack of time (30%), change in employment or completion of training (25%), and results that were not of statistical significance (15%).
Among the obstetrical randomized clinical trials registered and marked as completed on ClinicalTrials.gov, more than 40% were unpublished. Unpublished trials were more likely to be smaller studies, conducted by researchers who reported experiencing a lack of time as the most common barrier to study publication.
ClinicalTrials.gov 上注册的部分产科随机临床试验并未在同行评议期刊上发表。
本研究旨在比较 ClinicalTrials.gov 上注册的已完成的发表和未发表的产科随机临床试验的特征，并确定发表的障碍。
这项横断面研究从 ClinicalTrials.gov 中查询了 2009 年 1 月 1 日至 2018 年 12 月 31 日期间注册的所有已完成的产科随机临床试验。对于每一项已完成的产科随机临床试验，我们从 ClinicalTrials.gov 中提取了以下注册字段：ClinicalTrials.gov 标识符、招募状态、试验开始和完成日期、研究结果、干预类型、研究阶段、入组人数、资助类型、地点和设施。计算的变量包括完成时间。2021 年 5 月，我们使用 PubMed 和 Google Scholar 来确定已完成试验的发表情况，并比较了发表和未发表的随机临床试验的特征。未发表研究的相应作者的电子邮件地址是从 ClinicalTrials.gov 和部门网站收集的。2021 年 9 月至 2022 年 3 月期间，联系了这些完成但未发表的产科随机临床试验的作者，并邀请他们对一项检查发表障碍的感知的调查做出回应，收集并以计数和百分比的形式呈现这些回应。
在 ClinicalTrials.gov 上标记为已完成的 647 项产科随机临床试验中，有 378 项（58%）已发表，269 项（42%）未发表。未发表的试验更有可能入组人数<50 人（14.5%发表 vs 25.3%未发表；P<.001），且不太可能在多个地点进行（25.4%发表 vs 17.5%未发表；P<.02）。在未发表试验的作者的调查中报告的发表的主要障碍包括缺乏时间（30%）、工作变动或培训完成（25%）以及结果无统计学意义（15%）。
在 ClinicalTrials.gov 上注册并标记为已完成的产科随机临床试验中，超过 40%的试验未发表。未发表的试验更有可能是规模较小的研究，由报告缺乏时间是研究发表最常见障碍的研究人员进行。
