Is quality of life determined by expectations or experience?

Abstract

This is the first in a series of five articles The way we think about health and health care is changing. The two factors driving this change are the recognition of the importance of the social consequences of disease and the acknowledgement that medical interventions aim to increase the length and quality of survival. For these reasons, the quality, effectiveness, and efficiency of health care are often evaluated by their impact on a patient's “quality of life.” There is no consensus on the definition of quality of life as it is affected by health (health related quality of life). Definitions range from those with a holistic emphasis on the social, emotional, and physical wellbeing of patients after treatment1 to those that describe the impact of a person's health on his or her ability to lead a fulfilling life.2 This article assumes it to be those aspects of an individual's subjective experience that relate both directly and indirectly to health, disease, disability, and impairment. The central concern of this paper is the tendency to regard the quality of life as a constant. We contend that perceptions of health and its meaning vary between individuals and within an individual over time. People assess their health related quality of life by comparing their expectations with their experience. We propose a model of the relation between expectations and experience and use it to illustrate problems in measuring quality of life. The implications of these concepts for the use of quality of life as an indicator of the need for treatment and as an outcome of care are discussed. #### Summary points Health related quality of life is the gap between our expectations of health and our experience of it Perception of quality of life varies between individuals and is dynamic within them People with different …