Subjective quality of life: it's association with other constructs

The focus on assessing users' views as a way to evaluate healthcare interventions has increased the importance of quality of life as an outcome measure in psychiatric care. However, despite its wide use, little consensus seems to exist in the literature on the concept of quality of life and on its measurements. Although there is an agreement that it encompasses both objective and subjective indicators-the former referring to external living conditions and the latter describing one's appraisal of these conditions, the available literature shows that the two indicators are only weakly to moderately correlated. Inter-correlation between subjective constructs such as subjective quality of life, self-rated needs and self-rated symptoms has also been reported, suggesting the existence of a general subjective appraisal factor influencing all ratings of all those constructs. The factor summarizes a higher subjective quality of life and fewer needs and symptoms, and is affected by psychopathology, in particular mood symptoms. A challenge for future research is to identify how the general appraisal factor can be distinguished from the specific variance of subjective quality of life ratings that is independent of that factor. There seems to be a need for more research into the association of quality of life with other constructs and into the factors that mediate the associations described in the literature. This is likely to require more conceptual work and systematic studies using qualitative and quantitative methods.