The construct validity of subjective quality of life for the severely mentally ill.

Subjective quality of life is the individual's rating of his or her satisfaction with various domains of everyday living. Given the similarity of this construct with anhedonia due to depression, efforts to establish its construct validity vis-a-vis other psychiatric variables must partial out the influence of depression on subjective quality of life. Forty-nine patients with severe mental illness completed an interview-based measure of quality of life and measures that represent psychiatric symptoms, including depression, social functioning, social support, and intelligence. Findings from a multiple regression analysis suggested that depression, social adjustment, size of the support network, and verbal intelligence are independently associated with quality of life. This suggests that quality of life is not redundant with the anhedonia common to depression. Findings about the multifaceted nature of quality of life have implications for understanding the effects of treatment programs on the construct.