Can quality or quality-of-life be defined?

The aim of this paper is to examine the oft-heard concern that quality or quality-of-life cannot be defined. This concern persists today, even in the presence of countless studies that claim to be assessing quality or quality-of-life. There is obviously a disconnect here that warrants some attention, if not explanation. In this study, I summarize the extent of this disconnect and offer a number of potential explanations of why this situation exists. I review the role that operational definitions, statistical and empirical models, and content-specific definitions play in defining quality and/or quality-of-life. I conclude that none of these approaches provide a comprehensive definition of quality or quality-of-life. In its stead, I will argue that quality or quality-of-life represents a distinctive pattern of thinking. I establish this pattern by examining the cognitive-linguistic basis of these definitions and argue that when this is done it will be possible to identify an universal cognitive (hybrid) construct that describes how a person thinks about all types of qualitative assessments. The implication of this is that for a study to claim that it is defining or assessing quality or quality-of-life, it will first have to demonstrate the presence of the elements of this hybrid construct.