A double-blind study is a clinical trial with two groups of subjects who are treated with different drugs. In the process, one test group receives the actual drug to be investigated and the other group receives a placebo drug. The term “double-blind” means that neither the test subjects nor the treating physician know which preparation was administered to whom. Randomization also aims to evaluate the efficacy of the preparation as objectively as possible.
Nevertheless, to not jeopardize the safety of the subjects, an institution or physician not participating in the experiment must know about the correct administration of each subject’s preparation. The great advantage is that the results regarding efficacy and side effects remain uninfluenced by any medical opinion. Thus, well-founded, scientific results are provided. The disadvantage of double-blind studies is that treatment options are limited if physicians aren´t informed about the exact composition of the drug. Ethical reasons also lead to discussions. The risk is also mentioned that physicians would not be able to intervene quickly enough in an emergency. This is because they would first have to clarify queries with the independent institute or physician. For this reason, experiments of this form are more often conducted as so-called blind studies. Hereby, physicians know about the preparations, but the test subject remains “blind.