Background and aims: The purpose of this study was to revalidate the Persian version of the WHO
quality of life (WHOQOL-BREF) instrument to determine the quality of life status in the Shahrekord
Cohort Study (SCS) in the southwest of Iran. This study was designed to serve as one of the sources of
the Prospective Epidemiological Research Studies in Iran.
Materials and Methods: In this cross-sectional study, 2000 people were randomly selected from the
study population of the SCS. The reliability and internal consistency of the WHOQOL-BREF were
measured using Cronbach alpha coefficient and Pearson’s correlation. construct validity and factors
measured using Pearson’s correlation matrices with each of its domains. To measure the face, content,
and construct validities, the views of the panel of experts and exploratory factor analysis were used. In
addition, the validity of the questionnaire was evaluated using linear regression.
Results: All domains of the questionnaire met the minimum reliability standards (Cronbach alpha
and intra-class correlation >0.7), except for social relationships. The results of comparison analysis
indicated that the questionnaire discriminated well between subgroups of the study samples differing
in their health status. Regarding validity, the Kaiser-Meyer-Olkin (KMO) value was 0.94 and the value
of Bartlett’s test was 1699.01 (P≤0.001).
Conclusion: The findings suggested that WHOQOL-BREF is a reliable and valid measure of healthrelated
quality of life among SCS population.