A physician, who is responsible for the conduct of the clinical trial at a site, has to prove according to legal requirements his scientific qualifications and the adequacy of the facilities of his clinic or practice. Clinical trials can only be performed by those physicians who have the appropriate experience so that all important scientific aspects are considered.

The physician informs the subject in detail about the study including its procedures, potential benefits, purpose, risks and scope. The subject must also be informed that he/she has the right to leave the study at any time without giving any reasons and their questions be answered throughout the study. All unexpected adverse events reported by the subject, or observed by the investigator must be followed-up, if necessary, (in the case of serious adverse events) reported immediately to the sponsor and to the authorities.