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For Researchers is a registry and results database of publicly and privately supported research studies conducted in the United States and around the world. Sponsors or investigators of certain clinical trials are required by U.S. law to register their trials on and submit summary results to Other international policies also require trial registration. See the Why Should I Register and Submit Results? page for more information.

Each study record includes a summary of the study protocol, including the purpose, recruitment status, and eligibility criteria. Study locations and specific contact information are listed to assist with enrollment. See How to Read a Study Record to learn more about the information found in a study record.

Some study records include summary study results in a tabular format. The results information submitted to includes the number of participants starting and completing the study, baseline characteristics, outcome measures, and adverse events. See About the Results Database for more information.


Register a Study or Submit Results

The Submit Studies section of the site provides information for investigators who want to register a study, submit results, or update a study record. See the For Study Record Managers page for more information.

Find Studies on is updated daily. Please check the site frequently for new information.

The Find Studies section of the site includes different options for finding studies, along with instructions on how to find the studies you are looking for and how to read study records. In this section, you can:


The Resources section of the site includes scholarly publications by staff, news on clinical alerts, statistics about, and information on downloading content from the database.

See the Downloading Content for Analysis page for help with downloading large numbers of study records from the database in Extensible Markup Language (XML) or formats that are compatible with Microsoft® Excel such as comma-separated values (CSV) format.

Learn More

For Help With Registering a Study or Submitting Results

If you are a sponsor or investigator and have questions about registering a study or submitting results, contact staff at

For Questions or Comments About

To send the National Library of Medicine questions or comments about the site, use the Customer Support link at the bottom of any page.

Please note that the information in the study records on is provided by the organizations and people that sponsor and carry out the studies. For questions about a specific study, please contact the study research staff listed in the Contacts and Locations section of the study record.

This page last reviewed in November 2015