The prevention of hemorrhagic stroke. A review of the rational and ethical principles of clinical trials on unruptured intracranial aneurysms and arteriovenous malformations.

There is currently no evidence that preventive treatment of unruptured aneurysms or AVMs is beneficial and randomized trials have been proposed to address this clinical uncertainty. Participation in a trial may necessitate a shift of point of view compared to a certain habitual clinical mentality. A review of the ethical and rational principles governing the design and realization of a trial may help integrate clinical research into expert clinical practices. The treatment of unruptured aneurysms and AVMs remains controversial, and data from observational studies cannot provide a normative basis for clinical decisions. Prevention targets healthy individuals and hence has an obligation of results. There is no opposition between the search for objective facts using scientific methods and the ethics of medical practice since a good practice cannot forbid physicians the means to define what could be beneficial to patients. Perhaps the most difficult task is to recognize the uncertainty that is crucial to allow resorting to trial methodology. The reasoning that is used in research and analysis differs from the casuistic methods typical of clinical work, but clinical judgement remains the dominant factor that decides both who enters the trial and to whom the results of the trial will apply. Randomization is still perceived as a difficult and strange method to integrate into normal practice, but in the face of uncertainty it assures the best chances for the best outcome to each participant. Some tension exists between scientific methods and normal practice, but they need to coexist if we are to progress at the same time we care for patients.