What the response contains
Try diabetes, asthma, and migraine and use the returned fields to identify the right record.
Fields worth checking
- Science & Nature
- ClinicalTrials.gov results
- public source
ClinicalTrials.gov
Science & Nature · ClinicalTrials.gov results · public source
Live lookup
Type a real query, scan the cards and confirm the key details before opening the full source.
Quick examples
A record is not, by itself, a clinical result
The /api/v2/studies response separates protocolSection, derivedSection, and hasResults. In a test query, a study with overallStatus COMPLETED had hasResults false: a completed study and a record with posted results are different facts. Use a record to find the reported protocol and status, not to conclude that an intervention works or suits a person.
- Check hasResults before looking for outcomes in a record.
- Read eligibilityCriteria, contacts, and dates in the full study when a decision depends on them.
- Take health questions to a qualified professional; the API does not replace clinical advice.
Search and move through the list with the returned token
query.cond accepts a search condition, such as asthma, and pageSize sets the response size. When more studies exist, the API returns nextPageToken; it is the safe path to the next page. totalCount appears only when the request uses countTotal=true, so do not assume that number is always present.
- Store nextPageToken exactly as it appears in the response.
- Use countTotal=true only when an interface or analysis needs the total.
- Treat a 400 response as an invalid request and review parameters instead of repeating the token.
Request the needed fields and keep the NCT ID
The fields parameter can request specific parts, for example protocolSection.identificationModule.nctId and protocolSection.statusModule.overallStatus. The NCT ID identifies the study within its record and is more reliable for saving, comparing, or linking than a title. Check the update date and open the complete record whenever context matters.
- Use fields in recurring collections to reduce the received volume.
- Associate status and dates with the NCT ID, not just the study name.
- Do not turn recruitment status into a participation recommendation.