Objective Response: A measurable response.

Observational Study: A type of study in which individuals are observed or certain outcomes are measured. No attempt is made to affect the outcome (for example, no treatment is given).

Off Label: Describes the legal use of a prescription drug to treat a disease or condition for which the drug has not been approved by the US Food and Drug Administration.

Opiate: A drug used to treat pain. It contains opium or a substance made from opium (such as Morphine).