NAIRN S. Nursing Inquiry 2012; 19: 6–17 A critical realist approach to knowledge: implications for evidence‐based practice in and beyond nursingThis paper will identify some of the key conceptual tools of a critical realist approach to knowledge. I will then apply these principles to some of the competing epistemologies that are prevalent within nursing. There are broadly two approaches which are sometimes distinct from each other and sometimes inter‐related. On one side, there is the view that all healthcare interventions should (...) be judged on the principles of randomised controlled trials and the other is a preoccupation with language in which healthcare interventions are subjected to a discursive interrogation. These debates are configured through the idea of a hierarchy of knowledge that is accorded uncritical acceptance by some and virulent distaste by others. I will argue that the notion of hierarchy is problematic and is largely argued for in unproductive epistemological terms. What is required is a shift towards a theory that emphasises the contextual nature of the ways that knowledge is produced and disseminated. In other words, there is no single hierarchy of knowledge, but there are multiple hierarchies of knowledge. (shrink)