Before a product can be marketed as a drug in the US, it must receive approval from the Food and Drug Administration (FDA). FDA approval is granted only after a drug has undergone stringent clinical testing for effectiveness and safety, and the kind of studies which are most likely to lead to FDA approval are sometimes called "regulatory-quality" studies. Typically, such studies are randomized, placebo-controlled, double-blind, multi-site studies, in which the drug is shown to have a significant and reliable effect on treating, preventing or curing a disease or other medical or psychiatric condition.