Selective publication of complete studies or outcomes within studies hampers unbiased medical decision making. If the available body of evidence does not offer a fair representation of all existing evidence, the true effect of an intervention cannot be judged, possible harmful effects cannot be identified and unnecessary costs for healthcare may be invoked. Prospective registration of studies at their inception and public disclosure of all study results via result databases should be enforced on a worldwide scale in accordance with the fundamental and ethical obligations of the investigators towards study participants who were subjected to potential harm in the belief that they contributed to medical progress. These regulations will ensure a solid basis for fully evidence-based decision making in health care.