This paper challenges the traditional assumption that descriptive and prescriptive sciences are essentially distinct by presenting a study on the implicit normativity of the production and presentation of biomedical scientific facts within evidence-based medicine. This interdisciplinary study serves as an illustration of the potential worth of the concept of implicit normativity for bioethics in general and for integrated empirical ethics research in particular. It demonstrates how both the production and presentation of scientific information in an evidence-based decision-support contain implicit presuppositions and values, which prestructure the moral environment of the clinical process of decision-making. As a consequence, the evidence-based decision support did not only support the clinical decision-making process; it also transformed it in a morally significant way. This phenomenon undermines the assumption within much of the literature on patient autonomy that information disclosure is a conditional requirement before patient autonomy even starts; patient autonomy is already influenced during the production and presentation of information. These results imply an increased responsibility of those who produce and present evidence-based facts (i.e. scientists in general and physicians in particular). The insights of this study not only involve a different focus on both theory and practice of patient autonomy and informed consent, but they also call for a broader scope of morality than does traditional empirical research in bioethics. The concept of implicit normativity within integrated empirical ethics research calls for a strong cooperation between bioethicists and descriptive scientists, i.e., a cooperation that goes beyond the discipline-specific epistemic values and that takes place during all phases of the research process.