Clinical Trials FAQs

What are clinical trials?

Clinical trials are systematic investigations that assess the safety and efficacy of new medical interventions, including drugs, therapies, and devices. Conducted with human participants, these studies generate vital data that informs clinical practice and therapeutic guidelines. In the context of Embase, clinical trials provide valuable insights into the latest research developments and treatment options available in the biomedical field. They are essential for researchers and healthcare professionals seeking to stay informed about emerging therapies and evidence-based practices. They are used to support clinical evidence for Clinical Evaluation reports for medical devices, providing real world data (RWD) which supports Health Economics and Outcomes Research (HEOR), providing competitive intelligence, and insights for optimal clinical trial design, and much more.

What is ClinicalTrials.gov?

ClinicalTrials.gov is a comprehensive online database provided by the U.S. National Library of Medicine. It serves as a registry and results database for publicly and privately supported clinical studies conducted around the world. The database includes information on a wide range of clinical trials, including those investigating new drugs, therapies, medical devices, and treatment approaches across different medical conditions and patient populations.

What new content will be available in Embase from ClinicalTrials.gov?

Embase includes clinical trials obtained from ClinicalTrials.gov, significantly broadening the range of research materials to encompass more than 598,000 trials currently available in the database. Following the initial data load, we are bringing regular updates to ensure the content remains up to date.

How did we add this data?

We started adding approximately 20,000 clinical trials per day to Embase.com. This process took up to 6 weeks to complete, and all trials from ClinicalTrials.gov were fully loaded by June 16, 2025. We added another batch of 65k clinical trials between 13th October and 16th October. From April onward the clinical trial content is now kept current through daily updates.

How can clinical trial records be identified in Embase?

Previously, articles and clinical trial records appeared together in a single combined list in the results page. With the latest release, the results page is split into an articles tab and a clinical trials tab. The clinical trials will now appear only in a dedicated clinical trials tab on the new results page.

How can I exclude clinical trials from my search results based on queries?

To exclude clinical trials from your search results, add the following to your query:

• NOT 'clinical trial'/it
• NOT 'clinical trial':dtype

How can I search exclusively for clinical trials?

To search exclusively for clinical trials, add the following to your query:

• AND 'clinical trial'/it
• AND 'clinical trial':dtype

Can I use the field code jt to exclude or include clinical trials?

We recommend using one of the following queries to retrieve clinical trial content:

• 'clinical trial'/it
• 'clinical trial':dtype

Please note that 'clinicaltrials.gov'/jt will not be supported in the future as it will be intended solely for the articles and will not be applied to clinical trial records from clinicaltrials.gov. To ensure your saved searches will continue to work correctly once above change is made, we recommend updating your queries to use either the publication type (/it) or data type (:dtype) field instead.

'clinicaltrials.gov'/jt à 'clinical trial'/it

'clinicaltrials.gov'/jt à 'clinical trial':dtype

How can I search for specific clinical trial data ?

We have added dedicated field codes for searching within clinical trial data specifically (not just identifying that a record is a clinical trial). All these field codes support case-insensitive searches and wildcard characters. Add these to you search query to search for below specific clinical trial information.

Which field codes are shared between articles and clinical trials?

Some Embase field codes are shared across both the article results and the clinical trial results. When you use one of these common field codes in your query, Embase will searches for corresponding information in both articles and clinical trials content, hence the results will appear in both tabs. Use common field codes when you want to run a broad search across all content types.

How will free text search work?

If you enter a search term without specifying a field code, Embase will automatically performs a free text search across all searchable fields in both the article and clinical trial indexes. As a result, free-text searches will return results from both the Articles and Clinical Trials content types, depending on the search term. This search provides the broadest coverage and helps ensure that relevant records are not missed.

How do different search approaches affect where results are returned?

How can I filter clinical trial results using the new Clinical Trials tab?

We have added more filters to give users much finer control over how you search, filter, and review clinical trial content. We have introduced a dedicated clinical trials tab on the new results page with its own set of filters, letting you refine clinical trial results directly:

• Status
• Phase
• Study type
• Results reported (Yes/No)
• Adverse events reported (Yes/No)
• Location
• Sponsor
• Collaborator
• Age
• Sex/Gender
• Publication year (First submitted date)
• Drugs
• Disease
• Devices

You can apply multiple filters at once, and the results count next to the tab updates dynamically as filters are applied. The tab also includes 'More' and 'Export' options, consistent with the existing Articles tab.

What dates are shown for clinical trials record ?

Clinical trial records include the following dates in the Additional Information section:

• Entry date (the date when the trial record was added to Embase)
• Update date (marking any updates made to the record after it was added to Embase)
• Source publication date (First submitted date on clinicaltrials.gov).

Will clinical trials be included in my existing saved searches?

Yes, running existing saved searches generates results that include clinical trials along with other content types. If you do not wish to include clinical trials content, we recommend editing your saved searches to add the exclusion condition:

NOT 'clinical trial'/it OR NOT 'clinical trial':dtype

Will clinical trials be included in email alerts?

Clinical trials are not included in email alerts. We are not planning to include clinical trials in email alerts at this stage.

How will clinical trials be indexed in Embase?

Clinical trials were automatically indexed using the latest Emtree vocabulary at the time (Emtree 2026.2), ensuring that they were indexed accurately. More information is available here - Mapping of Clinicaltrials.gov fields to updated Embase Clinical trial details page | Embase Support Centeropens in new tab/window

How are NCT numbers and PUI linked?

PUI numbers for Clinical trial records are their respective NCT numbers prefixed by 'L', for example – LNCT12345678.

How can we use NCT number to search a particular clinical trial record?

Searching with an NCT number alone will retrieve all Embase records in which that NCT number appears anywhere in the indexed content, regardless of content type. To retrieve a specific clinical trial record imported from clincialtrials.gov, prefix the NCT number with "L" and search for it using the PUI field. This approach will return only the corresponding clinical trial record.

How long will it take to index a clinical trial record?

All clinical trial records are fully indexed (automatically) before they are published on Embase.

Will there be regular updates to the clinical trials data?

Yes. While the first release was a one-time data load of all trials from clinicaltrials.gov, clinical trial content is now updated daily since April 2026, delivered alongside article content.

Is clinical trial data available in Medline/Pubmed?

Pubmed/Medline only provide related published content (like journals) having any reference of the clinical trials. They do not provide content from clinicaltrials.gov.

What CT sponsor information is available in an Embase record?

Sponsor information is now available. As of Release 3, clinical trial records include sponsor data, and a dedicated (:ctsp/ctsp) field code that lets you search specifically within the sponsor field. Sponsor information also appears as a filter option in the new Clinical Trials tab.

How does the addition of clinical trials affect PV workflows?

Clinical trials are not included in the alerts. However, searches will have additional records from CT content and can be filtered out if not required from PV workflows, using the NOT 'clinical trial'/it OR NOT 'clinical trial':dtype query.

Are we linking a clinical trial with publications?

Users can easily identify all Embase records associated with a clinical trial by searching for the trial's NCT number. This search retrieves records that reference the specified clinical trial across Embase content. In addition, the Find Linked Articles feature is available on clinical trial records details page. This feature automatically runs a search to retrieve publications linked to the selected clinical trial, making it easier to discover related articles and evidence.

Is monitoring clinicaltrials.gov mandatory for clinical evaluation of medical devices?

It is advisable to visit clinicaltrials.gov for the latest developments & updates for medical devices.

How will clinical trials be returned in API queries?

Clinical trial records are included by default in responses from the Embase Article API. If you would like to exclude clinical trial records from your results, you can add one of the following filters to your query:

NOT 'clinical trial'/it OR NOT 'clinical trial':dtype

In addition, we are introducing a dedicated Clinical Trial API, which will enable users to retrieve clinical trial records directly and query trial-specific information. This API is designed to provide access to richer clinical trial content and metadata beyond what is available through the Embase Article API.

Where can I find more information about this new content addition?

For additional details or specific inquiries, please feel free to reach out to our support team or visit the Embase website for the latest updates. You can read more about this release here: Release Notes | Embase Support Centeropens in new tab/window