Quality of life in depression: An important outcome measure in an outpatient cognitive–behavioural therapy group programme?

Abstract

Studies have shown that psychiatric patients have significantly impaired quality of life (QOL) in comparison to community samples who are not suffering a mental illness. Despite an increase in research in the mental health field, there still remains little consensus as to the merit of using such questionnaires within a mental health population. There is a concern that QOL is redundant with affective state and symptomatology. We investigated the usefulness of the Quality of Life Enjoyment and Satisfaction Questionnaire-short form (QLESQ-SF) in a depressed outpatient sample receiving time-limited, standardized group cognitive-behavioural therapy. QLESQ-SF ratings were examined at admission and 10-week endpoint in an intention-to-treat (N = 212) and completers (N = 164) sample. QLESQ-SF ratings and symptom ratings (Beck Depression Inventory-II; Beck Anxiety Inventory) improved significantly over time. Hierarchical regression analyses revealed that, although affective state and change in symptomatology were significantly correlated with QOL and change in QOL, a large proportion of variance was unexplained. These results are inconsistent with the theory of measurement redundancy. QOL appears to be a useful measure that provides additional treatment outcome information distinct from affective state and symptomatology.