An open-label trial is a type of clinical trial in which both the researchers and participants know which treatment is being administered.^{[1] [2]} This contrasts with single blind and double blind experimental designs, where participants are not aware of what treatment they are receiving (researchers are also unaware in a double blind trial).

Open-label trials may be appropriate for comparing two very similar treatments to determine which is most effective. An open-label trial may be unavoidable under some circumstances, such as comparing the effectiveness of a medication to intensive physical therapy sessions.

An open-label trial may still be randomized. Open-label trials may also be uncontrolled, with all participants receiving the same treatment.

References

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