Hope for better treatment in participating clinical drug trials.

An informed consent is a prerequisite for participating in medical trials, whereby the person asked to take part in the trial shall understand what he is committing himself to, and that the consent is given voluntarily. Voluntariness can be undermined by so-called therapeutic optimism, i.e. belief in personal benefit brought about by the trial, as well as the difficulty of understanding how conventional treatment and the trial differ from each other, i.e. the so-called therapeutic misconception. The investigator, especially if he is also the attending physician, may influence the development of therapeutic misconception, because the participant may assume that the physician works as an investigator for the best benefit of the patients. It is important to recognize unrealistic optimism and therapeutic misconception of the trial, because for the participant they may result in disappointment and loss of confidence during the trial.