Quality of Well-Being Scale

The Quality of Well-Being Scale (QWB) is a generic measure of health-related quality of life (HRQOL) that combines preference-weighted values for symptoms and functioning. The QWB was developed in the early 1970s and is based on the general health policy model. In the general health policy model, a summary preference-based quality-of-life score is integrated with the number of people affected and the duration of time affected to produce the output measure of quality-adjusted life years (QALYs). QALYs combine morbidity and mortality outcomes into a single number.

In the original QWB, respondents report whether or not each of 27 symptoms were experienced on each of the 6 days prior to the assessment. Functioning is assessed by questions about the presence of functional limitations over the previous 6 days, within three separate domains (mobility, physical activity, and social activity). Unlike measures that ask about general time frames such as “the past 4 weeks” or “the previous month,” the QWB asks whether specific symptoms or functional limitations did or did not occur on a given day. Each symptom complex and functional limitation is weighted using preferences obtained from the ratings of 856 people randomly sampled from the general population. The four domain scores (three functioning, one symptom) are subtracted from 1.0 to create a total score that provides an expression of well-being that ranges from 0 for death to 1.0 for asymptomatic optimal functioning. References on the validation of the instrument are available from the University of California, San Diego, Health Outcomes Assessment Program (see Web site toward the end of [Page 805]this entry). The questionnaire must be administered by a trained interviewer because it employs a somewhat complex system of questions, including branching and probing. The original questionnaire takes about 15 minutes to complete on average. The authors believe the length and complexity of the original measure has resulted in its underutilization.

In 1996, a self-administered version of the questionnaire was developed to address some of the limitations of the original version. The Quality of Well-Being Scale–Self-Administered (QWB–SA) improves upon the original version in a number of ways. First, the administration of the questionnaire no longer requires a trained interviewer and can be completed in less than 10 minutes. Second, the assessment of symptoms follows a clinically useful review of systems model, rather than clustering symptoms based on preference weights. Third, a wider variety of symptoms are included in the QWB–SA, making it more comprehensive and improving the assessment of mental health.

Both the QWB and QWB–SA are available free of charge to users from nonprofit organizations. A small fee is charged to for-profit users. Information on copyright agreements and user manuals are available at http://www.medicine.ucsd.edu/fpm/hoap/.