Clinical trials are experiments or observations done in clinical research. Such prospective biomedical or behavioral research studies on human participants are designed to answer specific questions about biomedical or behavioral interventions including new treatments and known interventions that warrant further study and comparison. Clinical trials generate data on safety and efficacy. They are conducted only after they have received health authority approval in the country where approval of the therapy is sought. These authorities are responsible for vetting the benefit ratio of the trial their approval does not mean the therapy is 'safe' or effective only that the trial may be conducted.