Suitability of the WHOQOL-BREF for community-dwelling older people in Taiwan

Background: While life expectancy among older people has been lengthened due to improved public health and medical interventions, the importance of health-related quality of life in later life has also increased. However, the application of a generic health-related quality of life measure for older people needs to be carefully validated. Objective: To evaluate the practicality, reliability, validity, and responsiveness of the use of the brief version of the World Health Organization Quality of Life for people aged 65 years or older. Design: A prospective study. Methods: For a baseline assessment, 1200 community-dwelling older people living in Shin-Sher Township of Taichung County, Taiwan, completed the brief version of World Health Organization Quality of Life at their residences either by themselves or with the assistance of an interviewer. Furthermore, score changes in each health-related quality of life domain after a fall were followed up for assessing its responsiveness. Results: The average length of time required to complete the questionnaire was short (10.6 minutes for self-administration and 15.3 minutes for personal interview), and the score distribution in each domain was symmetrical with no floor or ceiling effect. Furthermore, all domain scores indicated excellent discriminant validity, construct validity, and responsiveness as well as good internal consistency and intra- and inter-observer test-retest reliabilities. Nevertheless, two items related to work capacity and sexual activity had higher missing values (4.5% and 16.5%) and poor interobserver test-retest reliabilities (0.43 and 0.20). Suggested modifications to the two items for older people are discussed. Conclusion: With a few modifications, the brief World Health Organization Quality of Life is a suitable health-related quality of life instrument for older people.