What is diabetes-specific quality of life (QoL), how important a concept is it, and how do we go about measuring it? To answer these questions, let us first consider the broad concept of health-related quality of life (HRQoL).
The medical community's interest in HRQoL, rather than the mere presence or absence of disease, has been growing at a phenomenal rate over the past few decades. As an illustration, note that the term quality of life was referred to in the medical literature approximately 40 times in the 8-year period between 1966 and 1974 versus more than 10,000 times in the 8-year period between 1986 and 1994.1 There can be little doubt that HRQoL is now a very hot topic—in diabetes as well as in most other areas of medical research.
The increasingly strong interest in evaluating HRQoL outcomes in clinical research is heartening. To a large degree, this interest reflects the growing recognition that HRQoL is, in the vast majority of cases, the single most important clinical and research outcome. The true impact of a successful medical intervention can be understood to largely reflect the degree to which said treatment has a positive influence on patients' immediate and/or future well-being. By emphasizing the assessment of HRQoL in medical research, health care providers are being subtly encouraged to give proper focus to patients' welfare. Consequently, medical research and care is slowly becoming more patient-focused, and there is a growing appreciation of the patient's perspective on health, disease, and medical treatments.
Unfortunately, clinical researchers in diabetes and other areas face a significant dilemma. Despite the growing pressure from funding agencies and/or government or institutional edicts to assess HRQoL, there is little agreement about how to do so. The concept of HRQoL remains ambiguous and poorly defined, and the number of different instruments that purport to assess the various aspects of this dimension is overwhelming.