[Ethics of medical scientific research: informed consent and the therapeutic misconception].

--Ethical approval of research involving human beings is based on two pillars: supervision of the scientific merit of the research and the risks and burdens for participants by an institutional review board (IRB) or the Dutch Central Committee on Research Involving Human Subjects (CCMO), and obtaining informed consent from the participant or his or her legal guardian. --Discussions on the ethical acceptability of a study generally focus on the first pillar, assessment by an IRB. The second pillar, obtaining informed consent, is often neglected. --Some ethical concepts play a role in obtaining informed consent, especially the concept of the 'therapeutic misconception', i.e. that participating in a study is the same as receiving individualised treatment from a physician. --Of importantance in this matter is the fundamental difference between the research relationship (between investigator and participant) and treatment relationship (between physician and patient). --Understanding the concept of therapeutic misconception is essential to explaining why it is often difficult to obtain valid informed consent from patients for medical research.