The purpose of this paper is to develop some thoughts on philosophical issues surrounding evidence-based medicine ( EBM), especially related to its epistemological dimensions. After considering the scope of several philosophical concepts that are relevant to the discussion, and drawing some distinctions among different aspects of EBM, we evaluate the status of EBM and suggest that EBM is mainly a meta-methodology. Then, we outline an evaluation of the thesis that EBM is a 'new paradigm' in the practice of medicine. We argue that EBM does not seem to have arisen in the way Kuhn imagined paradigms to arise but as a conscious, deliberate proposal, more as programme than as a reality. Furthermore, there is something paradoxical about appealing to evidence or to the best evidence as a way of promoting a new paradigm. For the proposal seems to assume that there is something that by its own virtue is the best evidence for a given time. But this idea would have been rejected by Kuhn. If EBM involves a genuine new alternative in the field of medicine and shows a way in which the discipline will endure henceforth, this indicates that it is not what Kuhn once called a 'paradigm' and even, paradoxically, it is good evidence that scientific paradigms do not exist, at least in medicine. [ABSTRACT FROM AUTHOR]