Clinical trials are valuable in guiding evidence-based practice in medicine.1 Oncologists' decision-making regarding therapeutic regimens generally depends on information from publications in peer-reviewed journals, the main channel through which trial results are publicly disclosed and communicated.2 Thus, the reporting quality of publications is of vital importance to ensure accurate dissemination of evidence.3,4
ClinicalTrials.gov is the largest publicly accessible trial registry, and the only one with a results database.5,6 In September 2007, the FDA Amendments Act (FDAAA; section 801) was passed mandating the timely reporting of results of applicable clinical trials to ClinicalTrials.gov,7 which greatly expanded the legal requirements for the public reporting of trial results and enhanced reporting transparency. In contrast to peer-reviewed publications, which might be subject to the selective judgments of editors and reviewers, information posted on ClinicalTrials.gov goes through a quality assurance (QA) process when required information is missing or internally inconsistent.
Cancer is a major public health problem worldwide and is the leading and second-leading cause of death in China and the United States, respectively.8,9 The interpretation and accuracy of trial results are of particular concern in medical oncology, in which therapeutic regimens are often rapidly developed and prompt treatment decisions are important for saving lives. So how accurately does the published literature convey information to the oncologic community regarding the efficacy and safety of cancer drugs assessed in clinical trials?
Currently, only one study has investigated the reporting consistency between ClinicalTrials.gov result database and publications.10 However, trials included in the study were completed before January 1, 2009—2 years after the enactment of mandatory result reporting law—and only 5 trials (3%) related to oncology. The accuracy of published literature conveying information to the oncologic community on cancer drug trials remains unknown. Has reporting consistency improved in the 10 years since the mandatory reporting laws were enacted?
To address these questions, we included cancer drug trials with results posted on ClinicalTrials.gov and that were completed between 2004 and 2014. Our study had 2 objectives: to identify the degree of completeness and consistency of results reported between the ClinicalTrials.gov database and the subsequent publications, and to identify the trends of reporting quality and associated characteristics.
We would like to thank the staff members of the National Library of Medicine and NIH, and their colleagues across the United States, who have been involved with the development and maintenance of ClinicalTrials.gov. We thank the Clinical Trials Center, Sun Yat-sen University Cancer Center, for assistance in data interpretation.
The authors have disclosed that they have no financial interests, arrangements, affiliations, or commercial interests with the manufacturers of any products discussed in this article or their competitors.
This work was supported by grants from the National Natural Science Foundation of China (No. 81372409), the Science and Technology Project of Guangzhou City, China (No.132000507), the National Natural Science Foundation of China (No. 81402532), and the National Natural Science Foundation of China (No. 81572962).
See JNCCN.org for supplemental online content.
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