Longitudinal investigation of the stable and dynamic components of the World Health Organization Quality of Life Measure (WHOQOL-BREF) using generalizability theory

The WHOQOL-BREF is a widely used 26-item self-report measure of Quality of Life (QOL), but there is lack of research investigating to what extent it measures dynamic (state) and stable (trait) aspects of QOL. Generalizability Theory is the most suitable method to examine the state-trait distinction and to evaluate the overall reliability and generalizability of the WHOQOL-BREF. Generalizability theory was applied to a longitudinal study dataset...