a drug clinical trial in which both the researchers and the patient know the identity of the test drug

A study in which all parties (patient, physician, and study coordinator) are aware of the treatment assigned. In an open-label study, no participants are given placebos. These are usually Phase I or II studies.

A study in which all parties, (patient, physician and study coordinator) are informed of the drug and dose being administered. In an open-label study, none of the participants are given placebos. These are usually conducted with Phase I & II studies.