Evidence, Research, Knowledge: A Call for Conceptual Clarity

Objective: To dispel some of the conceptual confusion in the field of evidence-based practice that has resulted from the overlapping use of the terms research, evidence, and knowledge. Approach: Theoretical discussion. Findings: Often the terms research and knowledge are used as synonyms for evidence, but the overlap is never complete. The term evidence has long been understood to mean the findings of research. Discussion: Recent attempts to broaden the definition of evidence to include clinical experience and experiential knowledge have been misguided. Broadening our understanding of the basis for clinical decision making and conceptualizing evidence are quite different tasks. Other factors (not other forms of evidence) do shape the clinical decision-making process, but they are not evidence. We might better term them knowledge. Confusing evidence with these other factors has hindered research and the improvement of clinical decision making in health care. We argue that this confusion results from the use of the term evidence when we really mean either research findings or knowledge. Conclusions: In this article, we have argued for specificity in the use of the term evidence. We urge the restriction of the term evidence to research findings, and while we acknowledge the importance of other influences on the clinical decision-making process, we insist that they are not evidence. The time has come to value personal experience and experiential knowledge for what they are—we should not have to disguise them as types of evidence for them to be deemed of any value. Being specific to language, the goal is to improve clinical decision making by increasing practitioners' reliance on research findings (evidence) while acknowledging (and valuing) the important part played by other forms of knowledge in the decision-making process. The distinctions are important.