Clinical Trials
A trial map pin is a starting point: read the dates and eligibility in the source record
2026-09-24 ยท 3 min read
A pin on a research map answers one question: where a study record lists a location. It cannot tell you whether that site is currently taking participants or whether you meet its participation criteria. The most useful next step is to open the linked ClinicalTrials.gov record and keep its NCT number visible as you read.
Read the dates as different kinds of information
Three dates are easy to blur together. Study start refers to the first participant's enrollment; a future date may still be an estimate. Primary completion is when data collection for all primary outcome measures finishes for the final participant. Study completion extends to the final collection of primary and secondary outcomes and adverse-event data. ClinicalTrials.gov labels these dates estimated or actual. An estimated date is a plan, so do not turn it into a promise that enrollment will open, end, or produce results on that day.
The record also has study record dates. These describe when information was submitted and posted. They help you see when the listing changed; they are different from the dates when participants are seen. A recent posting does not, on its own, confirm that every site or criterion still applies. The organisation responsible for the record supplies the study information, and ClinicalTrials.gov notes that records can lag behind a study's situation.
Read the criteria in full, then keep the uncertainty
Under Participation Criteria, look beyond the broad age or condition labels. Read the inclusion and exclusion text together. A study may specify a particular diagnosis, prior treatment, timing, or other requirements that a map filter cannot express. A criterion that seems to match you is a reason to ask the study team a question, not an eligibility decision. The team determines whether someone can participate through its own process; a registry or map cannot make that decision.
If the record lists several facilities, check Contacts and Locations for the specific one you had in mind. The same study can have different location entries, and a city pin alone is not a current invitation. Our guide to sponsor, site and contact details explains which listing to use when you want to ask a study-specific question. ClinicalTrials.gov also says that some studies add locations later and that participation may be in person or remote depending on the study design. The contact can clarify the practical details.
A five-line note to take away
Before sharing a listing, write down its NCT number, the date you checked it, whether each key date is estimated or actual, the criteria you need clarified, and the contact for the relevant location. That note makes it easier to revisit the source record if the map or registry changes. For the distinction between a study's overall label and a particular facility, see our status guide.
The map helps you find a record; it does not enroll you or recommend a treatment. If participation is on your mind, ClinicalTrials.gov advises discussing the study with your health care provider and contacting the study team for questions about its criteria.