Obesity and Quality of Life
JACOB C. SEIDELL
MARJA A. R. TIJHUIS
Health was defined by the World Health Organization (WHO) in 1947 as a state of complete physical, psychological, and social well-being. The concept of “quality of life” was developed to measure self-perceived health and can be interpreted as the individual’s overall satisfaction with life. Fontaine and colleagues refer to health-related quality of life as the subjective evaluation by the patient of the effects of medical conditions on physical and mental functioning and well-being.
Many questionnaires have been developed to measure quality of life. The most frequently used are currently the Quality of Well-Being scale (QWB), consisting of 50 questions, the Nottingham Health Profile (NHP), consisting of 45 self-administered items, and the Medical Outcomes Study Short Form-36 Health Survey (SF-36). The latter, a well-validated, 36-item questionnaire, provides a comprehensive measure of physical, emotional, and social well-being. This chapter primarily reviews studies using the SF-36, so that results between different populations can be compared.
The SF-36 measures nine health concepts: physical functioning (10 items), role functioning limitations due to poor physical health (4 items), bodily pain (2 items), general health (5 items), vitality (4 items), social functioning (2 items), role functioning limitations due to poor emotional health (3 items), mental health (5 items) and health change in the past year (1 item). A score can be calculated for each concept, with a low score indicating poor health and a high score indicating good health. These scores can be standardized, so that they range from 0 to 100 and can be more readily compared across health concepts. Such a standardized score is calculated as follows: