Quality of life assessment: validation of the Italian version of the WHOQOL-Brief

Abstract

SummaryObjective – To test the psychometric properties of the Italian version of the WHOQOL-BRIEF (e.g., construct and internal validity, concorrent validity with the MOS SF-36 and test-retest reliability). The WHOQOL-BRIEF is a 26-items self-report instrument which assesses four domains assumed to represent the Quality Of Life (QOL) construct: physical domain, psychological domain, social relationships domain and environment domain, plus two facets for assessing overall QOL and general health. Methods – Data have been collected in three sites (Bologna, Modena and Padua), located in the North of Italy, in the framework of the international WHOQOL project. According to the study design, the sample had to include about 50% males and 50% females, 50% of subjects below and 50% above the age of 45, all in contact with various health services. A subsample has been re-interviewed after 2-3 weeks in order to study test-retest reliability. After the WHOQOL-BRIEF, most subjects have also been administered the MOS-SF36 in order to test the concurrent validity between these two instruments. Results – The instrument was administered to 379 subjects (1/6 healthy and 1/6 sick), chosen to be representative of a variety of different medical conditions. Seventy patients, wTio displayed stable health conditions, have been reassessed after 2-3 weeks to study test-retest reliability. The WHOQOL-BRIEF domains has shown good internal consistency, ranging from 0.65 for the social relationships domain to 0.80 for the physical domain; it has been able to discriminate between in- and out-patients and between the two age groups considered in the present study (<45, ≥45 years). Only physical and psychological domains were found to discriminate between healthy and ill subjects. No gender differences in the mean scores for the four domains were found. Concurrent validity between the WHOQOL-Brief and the MOS-SF-36 was satisfactory, and specific for the physical and psychological health domains. Test-retest reliability values were also good, ranging from 0.76 for the environment domain to 0.93 for the psychological domain. Conclusions – This study shows that the WHOQOL-BRIEF is psychometrically valid and reliable, and that it is also potentially useful in discriminating between subjects with different health conditions in clinical settings.