Registration on (NCT number) is a worldwide registry and results database of publicly and privately supported clinical studies with human participants.


The National Library of Medicine (NLM) at the National Institutes of Health (NIH) maintains the website. It relies on the sponsors and principal investigators of clinical studies to provide and update information on the site. Usually the sponsor and/or PI will register on when they begin and update the information throughout the study. Investigators also may be required to report study results. There is no fee to register a study.

Why do we need to register on

Currently, you must register on if your study meets the FDAAA 801 definition of an "applicable clinical trial." While not always required, we generally recommend that all drug or device trials be registered.

Additionally, you must register if you plan to publish in journals. The International Committee of Medical Journal Editors (ICMJE) requires all trials be registered before they would publish research results generated by a clinical trial.

Learn more about the FDA definition of an "applicable clinical trial."

On this page:


Lynn Jagodzinski

(716) 888-4843 

FDA definitions

Learn more about FDA definitions of applicable clinical trials.

Who do we work with to register on

For questions regarding registration, contact: Lynn Jagodzinski

How do we register on

The site uses a web-based data entry system called the Protocol Registration and Results System (PRS) to register clinical studies and to submit results information for registered studies. You must have a PRS account to register study information on

Before applying for a PRS account, you should ensure that you are the appropriate individual to submit clinical study information to To avoid duplicate registration, studies should be registered only by the responsible party. To help you determine who is responsible for registering a study and submitting results, see the Elaboration of Definitions of Responsible Party and Applicable Clinical Trial (PDF). establishes one PRS account per organization (such as a company, university or medical center). All investigators from that organization who are conducting studies would be designated as users of this single PRS account. UB’s PRS account is SUNYBuffalo. 

You can contact the UB PRS Administrator, Lynn Jagodzinski, to request a user login. Please provide the following information for account set up:

  • Your full name
  • Login name
  • Email address (email that you use frequently)
  • Phone (phone that you use frequently)

Learn more on how to submit studies.

How long does it take to register on

Completion time depends on the complexity of the study being registered.

Notes / Additional References

Note:  The National Clinical Trial (NCT) number is another term for the registry number unique to each record. The format for the registry number is “NCT” followed by an 8-digit number, e.g.,: NCT00000419.