Definitions of Quality of Life: What Has Happened and How to Move On

TLDR

Quality of life is a key outcome in spinal cord injury rehabilitation, yet its definition and measurement remain unclear, despite influential models such as Dijkers’s framework. This article aims to trace the evolution of QOL and HRQOL concepts, catalog their definitions and measurement approaches, and offer guidance for clearer, more consistent QOL research. The authors conducted a narrative review of the QOL literature. The review traced the term “quality of life” back to WHO’s 1948 definition, highlighted ongoing confusion from the use of “well‑being,” noted persistent difficulties in consistently applying and categorizing QOL measures—especially for spinal cord injury—and urged researchers and readers to explicitly define and examine the specific measures employed.

Abstract

Background: Quality of life (QOL) is an important outcome in spinal cord injury (SCI) rehabilitation, but it is unclear how to define and measure it. Objective: The aims of this article are to (a) show how the concepts of QOL and health-related quality of life (HRQOL) have evolved over time, (b) describe the various ways QOL has been defined and measured, and (c) provide recommendations on how to be as clear and consistent as possible in QOL research. Method: A narrative review of the QOL literature was performed. Results: Roots of the term "quality of life" in health care can be traced back to the definition of health by the World Health Organization in 1948. The use of the word "well-being" in this definition is probably a main factor in the continuing confusion about the conceptualization of QOL. Within the field of SCI rehabilitation, the Dijkers's QOL model, distinguishing between utilities, achievements, and subjective evaluations and reactions, has been very influential and the basis for several reviews and databases. Nevertheless, literature shows that it is still difficult to consistently use the term "quality of life" and categorize QOL measures. Several aspects of QOL that are specific for individuals with SCI have been identified. Conclusions: Researchers should be as specific and clear as possible about the concept and operationalization of QOL in their studies. Readers should not take the term "quality of life" for granted, but should inspect the topic of the study from the actual measures used.