Toward an understanding of the quality of life construct: Validity and reliability of the WHOQOL-Bref in a psychiatric sample

• Evidence for the validity, reliability and dimensionality of the WHOQOL-Bref in a psychiatric sample.
• Valuable tool to be incorporated as part of routine of clinical/mental health services evaluation.
• A conceptual distinction between physical/level independence domains is suggested (as in WHOQOL-100).

This study tested the psychometric properties of the WHOQOL-Bref by examining its construct validity, predictive validity and reliability in a psychiatric sample. The sample consisted of 403 participants recruited from mental health care facilities. Construct validity was assessed through confirmatory factor analysis (CFA) and item-domains correlations. Predictive validity was evaluated via multiple regressions. Internal consistency was analyzed by using Cronbach's alpha. Results from CFA second-order hierarchical model and item-domain correlational analyses supported the construct validity of the WHOQOL-Bref. A 5-domain model (psychological, physical, social relationships, environment and level of independence) demonstrated good-fit and adequate internal consistency. Multiple regression analyses of the domains with overall quality of life (QOL), general health and general QOL were supportive of predictive validity. This study found support for the multidimensionality of the WHOQOL-Bref which demonstrated appropriate properties for the assessment of QOL in psychiatric inpatients and outpatients. Thus, a valuable tool to be incorporated as part of the routine clinical evaluation, monitoring and an important indicator of treatment outcome and research. Our findings suggest a conceptual distinction between the physical domain and level of independence domain in this short version of the WHOQOL, as proposed by the WHOQOL-100.