- Prior participation: are currently enrolled in, or have participated in, an interventional medical, surgical, or pharmaceutical drug or device or off-label use study (an investigational study in which a medical or surgical treatment was given) within 30 days prior to entry into the study, or persons who have previously completed or withdrawn from this study (after having signed the informed consent document). Participants may be ineligible if they are concurrently enrolled in any other type of medical research judged not to be scientifically or medically compatible with this study