Study Type

There are three types of studies available in ClinicalTrials.gov:

Interventional:

Studies where individuals are assigned to receive specific interventions. Participants may receive diagnostic, therapeutic or other types of interventions. Assignment of the intervention may or may not be random. Individuals are tracked and biomedical and/or health outcomes are assessed.

Observational:

Studies without an intervention. Studies where biomedical and/or health outcomes are assessed in a pre-defined group of individuals. Participants may receive diagnostic, therapeutic, or other interventions, but the investigator does not assign specific interventions to the participants of the study.

Expanded Access:

Records describing the procedure for obtaining an experimental drug or device for patients who are failing on currently available treatments for their condition and also are unable to participate in ongoing clinical trials. Expanded Access records are used to register all types of non-protocol access to experimental treatments, including protocol exception, single-patient IND, treatment IND, compassionate use, emergency use, continued access and parallel track.