Updated Analysis of Pediatric Clinical Trials Registered in ClinicalTrials.gov, 2008-2019

Background: Since the national clinical trials registry (ClinicalTrials.gov) launched in February 2000, more than 300,000 trials have been registered. However, little is known about the registered pediatric clinical trials with regarding to characteristics, trends and quality over time. Methods: To describe patterns of the registered pediatric clinical trials, a dataset of trials involving children was downloaded from ClinicalTrials.gov on August 1st, 2020. To further trace the registration of pediatric disease types, we selected the top four infectious diseases to describe their trends over time. To examine reporting completion rate of clinical trial results, we identified completed studies and then observed the proportion of trials subject to reporting. Results: Between 2000 and 2019, a total of 53,060 pediatric trials were registered at ClinicalTrials.gov, including 36,136 (68.1%) interventional trials and 6,692(31.5%) observational trials. The number of them increased significantly over time. Meanwhile, the number of missing data elements has generally declined.Most interventional pediatric trials were single center (61.4%), small-scale(58.9%), randomized (66.0%), and none masking(56.9%), with fewer drug trials being conducted over time.Many pediatric clinical trials were funded by other organizations.The proportion of trials complianced with reporting results varied by study type, trial phase and lead sponsor. Conclusion: The pediatric clinical trial registration are on the rise, with significant changes in registration information such as trial type, main purpose, and intervention characteristics, which can help stakeholders inform the decision to conduct trials in children. Although the proportion of missing data was decreasing, the proportion of reporting results remained to be improved.