Clinical trial

A clinical trial in medicine is a research study that evaluates new drugs or medical therapies to patients in strictly scientifically controlled settings.
Synonyms: clinical studies, research protocols, medical research
The purpose of such trials is to determine whether one or more treatment options are safe, effective, and better than current standard care. They are designed to be ethical, they must involve the full and informed consent of participating human subjects and they are closely supervised by the appropriate authorities.

Currently most clinical trial are designed to be randomized, double-blind, and placebo-controlled. This means that each study subject is randomly assigned to receive one of the treatments, which might be the placebo. Neither the subjects nor scientists involved in the study know which study treatment is being administered to any given subject; and, in particular, none of those involved in the study know which subjects are being administered a placebo.

Most clinical trials require large numbers of participants and sometimes it is necessary to organize multicenter clinical trials. Often the centres taking part in such trials are in different countries (in which case they are termed international clinical trials).