Content validity, construct validity, and reliability of the WHOQOL-Bref in a population of Dutch adult psychiatric outpatients

In this study, the psychometric properties of a quality of life scale, the WHOQOL-Bref, were examined in a population of 533 Dutch adult psychiatric outpatients. Participants underwent two semistructured interviews in order to obtain Axis-I and II diagnoses, according to DSM-IV. Besides the WHOQOL-Bref they also completed questionnaires for measuring psychopathological symptoms (SCL-90) and perceived social support (PSSS). Scores on 25 of the 26 questions of the WHOQOL-Bref had a good distribution. Similar to previous findings, exploratory factor analysis revealed a four-factor structure. A priori expected associations were found between the domains of the WHOQOL-Bref, on the one hand, and dimensions of the SCL-90 and the PSSS-score, on the other hand, indicating good construct validity. The internal consistency of the four domains of the WHOQOL-Bref ranged from 0.66 to 0.80. Domain scores of the WHOQOL-Bref correlated around 0.92 with the WHOQOL-100 domain scores. Relatively low correlations were found between demographic characteristics (age and sex) and WHOQOL-Bref domain scores. It is concluded that the content validity, construct validity, and the reliability of the WHOQOL-Bref in a population of adult Dutch psychiatric outpatients are good. The WHOQOL-Bref, therefore, is an adequate measure for assessing quality of life at the domain level in a population of adult psychiatric outpatients.