A specific problem arises in testing the effects of medications (or other forms of intervention) in randomized control studies .Here people with a diagnosis are randomly allocated to an interventions group (receiving instead a placebo without effect which means no treatment).Is it ethically justified to deprive this second group of a treatment or to give it to them only after the and of the study. Should you do randomized studies in such cases in particular if it is about a serious or life threatening disease.