An estimated 42.7 million Americans (15% of the population) had some form of arthritis in 1995 and, due to the increasing average age of the population, this total is expected to rise to 59.4 million (18.2%) by the year 2020(1,2). Consistent with this, it was recently estimated that, since 1990, the prevalence of arthritis has increased by 750,000 cases per year(3). The estimated total economic cost to the United States of arthritis is over $65 billion annually(4). Although the pain treatment american arthritis association medical and economic consequences of arthritis are of great concern to researchers and clinicians, this disease also affects an individual's capacity to live a full and active life. Thus, it has increasingly become clear that the problems associated with arthritis are not simply medical ones; it also appears to have a substantial impact on a person's functional capacity and quality of life(5). (top of page) Definitions of Quality of Life Many terms are used interchangeably (e.g., pictures of rheumatoid arthritis american arthritis association quality of life, health status, health-related quality of life) to discuss the effect of diseases, such as arthritis, on functioning and sense of well-being. At the broadest level, quality of life refers not only to health status, but also to environmental and economic factors (e.g., income, educational attainment) that can substantially influence well-being. Thus, different conceptual frameworks guide how quality of life is defined and measured(6). For example, investigators who are interested in the evaluation of the quality of american arthritis association american arthritis association medical care outcomes tend to place greater emphasis on the development of measures that focus on overall well-being. In contrast, those operating from a medical ethics perspective tend to develop measures assessing the importance that an individual places upon his/her quality of life. As a result, there are hundreds of tests purporting to measure different aspects of quality of life(7). However, when the focus is on the impact of a disease or medical condition on functional health status and woodworking joints american arthritis association well-being as
