 Historically in many cultures there has been a shift from paternalism, the view that the "doctor always knows best," to the idea that patients must have a choice in the provision of their care and be given the right to provide informed consent to medical procedures.There can be issues with how to handle informed consent in a doctor–patient relationship; for instance, with patients who do not want to know the truth about their condition.Furthermore, there are ethical concerns regarding the use of placebo.