How to Read a Study Record


Study Record Details

At the top of a study record page, you will find the study brief title and the following information:

Study Status

  • Studies with an open recruitment status, such as "Recruiting," "Not yet recruiting," or "Available for expanded access," display their status in green text.
  • Studies with a closed recruitment status display their status in red text. This status includes studies that have been completed and studies that are ongoing but not recruiting participants.
  • Studies with an Unknown status display their status in brown text.

See Recruitment Status in the glossary for more information.


The organization or person (see Sponsor-Investigator) who oversees the clinical study and is responsible for analyzing the study data.


A collaborator is an organization other than the sponsor that provides support for a clinical study. This may include funding, design, implementation, data analysis, or reporting.

Information Provided By (Responsible Party)

The contents of the study record are provided by this person or organization. This sponsor, sponsor-investigator, or sponsor-designated principal investigator is responsible for submitting information about a clinical study to and updating that information. Identifier (NCT Number)

A unique identification code given to each clinical study registered on The format is the letters "NCT" followed by an 8-digit number (for example, NCT00000419).

You can quickly find a record on by entering this identifier in the search box located at the top of each page or on the home page.

First Received Date

The first received date is the date that summary clinical study protocol information was first submitted to the registry. There may be a delay of a few days before the study information is available on

Last Updated Date

The last updated date is the most recent date that changes to study information were submitted to There may be a delay of a few days to a few weeks before the updated study information is available on This date may be different from the last verified date.

Last Verified Date

The last verified date is the most recent date that all of a clinical study's information on was confirmed as accurate and up to date. This date may be different from the last updated date. If a study with a status of Recruiting; Not yet recruiting; or Active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as Unknown.


Information in a record can be modified at any time by the sponsor or investigator. If no changes have been made, "No changes posted" appears in this field. If changes have been made, earlier versions of the record can be accessed by clicking on the "History of Changes" link that appears in the field. For more information, see Historical Views of Records.

Study Record Tabs

You can view information about a study by using the Full Text View, Tabular View, and Study Results (or No Study Results Posted) tabs:

Study record page tabs

Full Text View

The Full Text View is the default view. It provides complete information about a study, including:


This section explains what the researchers will do during the clinical study and why they are conducting the study, including what condition is being studied and the questions that the researchers want to answer. General information, such as estimated enrollment and study start and completion dates, is also provided. You can find out what type of intervention participants receive, what the dosage is for drugs, and how long the participants receive the intervention. Details such as phase, study type, study design, and official study title are provided.


This section explains who is allowed to participate in the study. The most common criteria are listed first: ages eligible for study, genders eligible for study, and accepts healthy volunteers. A list of additional inclusion and exclusion criteria is also provided in this section.

Contacts and Location

This section contains the study's Identifier (NCT Number), contact information for the study investigators. The study location is shown below the study sponsor's contact information. If the study is being conducted in many locations, click on the Show Study Locations link to see a complete list of locations. The recruitment status appears next to each location.

More Information

This section contains information on references and links to Web sites that are relevant to the study. The study sponsor may provide citations for publications that are related to the study background or the results of the study.

Tabular View

The Tabular View displays complete study information in a table format. The information is organized as follows:

  • Tracking information (for example, Start Date, Primary Outcome Measures)
  • Descriptive information (for example, Brief Summary, Study Design)
  • Recruitment information (for example, Recruitment Status, Eligibility Criteria)
  • Administrative information (for example, Identifier (NCT Number), Responsible Party)

Study Results

If results for a study are available in the results database, the Study Results tab provides summary results for the study. Study results include the following information:

If no results have been posted on, the Study Results tab is labeled "No Study Results Posted." For more information, see About the Results Database.

Search Term Highlighting

If you are viewing a study record that appeared in your search results list, your search words will be highlighted in the text of each of the study records found by your search. Search words will be highlighted in pink, and synonyms for search words will be highlighted in yellow. For example, if your search words are heart attack, the words heart and attack will be highlighted in pink wherever they appear in each record. Synonyms for heart attack, such as myocardial infarction, will be highlighted in yellow.

Highlighted search term and synonym

Historical Views of Records

Historical views of all records are available through the archive site. Historical views show you when a record was updated and how it was changed. You will need the Identifier (NCT Number) for the record whose history you want to view. The NCT Number can be found at the top of every study record. You can also click on the "History of Changes" link at the top of a study record to see its earlier, archived versions.

For Advanced Users: Viewing Study Records in Extensible Markup Language (XML) Format

You can add the URL parameter "displayxml=true" to the end of a "search request" URL to display the search results list in XML in your browser:

By default, this option will return the first 20 search results. A parameter such as "count=100" can be used to retrieve the first 100 results. You can also use a parameter such as "start=101" to retrieve studies after the first 100 results.

In the following example, all three parameters are used to retrieve search results ranked 1201–1400 that are found by a search on the term "cancer":

For more information, see Downloading Content for Analysis.

Learn More

This page last reviewed in August 2012