| Votes | By | Price | Discipline | Year Launched |
| Ben Goldacre, Open Knowledge International | FREE | Clinical Research |
OpenTrials is an open-data initiative aimed at bringing transparency and accountability to clinical research by aggregating information about clinical trials from multiple sources into a single, searchable platform. Developed by Open Knowledge International in collaboration with Evidence-Based Medicine Foundation, the project collects and links trial registrations, results, publications, regulatory documents, and data on adverse events—helping researchers, journalists, and patients identify missing data, inconsistencies, and reporting gaps. Although the platform is no longer under active development, OpenTrials remains an important demonstration of how open data can expose issues in clinical trial reporting and support evidence-based medicine. Its legacy continues to influence broader movements advocating for trial transparency, such as AllTrials, and serves as a model for how public, linked databases can improve trust and oversight in biomedical research.