ORIGINAL PAPER Psychometric Properties of the WHOQOL-BREF in an Iranian Adult Sample A. R. Usefy • Gh. R. Ghassemi • N. Sarrafzadegan • S. Mallik • A. M. Baghaei • K. Rabiei Received: 14 June 2008 / Accepted: 28 December 2009 Ó Springer Science+Business Media, LLC 2010 Abstract To evaluate discriminant validity, reliability, internal consistency, and dimensional structure of the World Health Organization Quality of Life-BREF (WHOQOL-BREF) in a heterogeneous Iranian population. A clustered randomized sample of 2,956 healthy with 2,936 unhealthy rural and urban inhabitants aged 30 and above from two dissimilar Iranian provinces during 2006 completed the Persian version of the WHOQOL-BREF. We performed descriptive and analytical analysis including t-student, correlation matrix, Cronbach’s Alpha, and factor analysis with principal components method and Varimax rotation with SPSS.15. The mean age of the participants was 42.2 ± 12.1 years and the mean years of education was 9.3 ± 3.8. The Iranian version of the WHOQOL- BREF domain scores demonstrated good internal consis- tency, criterion validity, and discriminant validity. The physical health domain contributed most in overall quality of life, while the environment domain made the least contribution. Factor analysis provided evidence for con- struct validity for four-factor model of the instrument. The scores of all domains discriminated between healthy per- sons and the patients. The WHOQOL-BREF has adequate psychometric properties and is, therefore, an adequate measure for assessing quality of life at the domain level in an adult Iranian population. Keywords Reliability Á Construct validity Á Internal consistency Á Discriminant validity Á WHOQOL-BREF Introduction Quality of life incorporates humanistic elements of health and well being and is one of the criteria in the evaluation of health care delivery system, assessment of treatment and evaluation of cost-effectiveness (WHOQOL Group 1993). Instruments on quality of life and functioning instruments abound in health care literature, ranging from simple to complex. Researchers have invariably incorporated an array of subjective and objective indices which measure impact of disease and impairment on daily activities and behavior, perceived health measures and disability/func- tioning-status (Bergner et al. 1981; Hunt et al. 1989; Ware et al. 1993). A short version of the World Health Organi- zation Quality-100 called WHOQOL-BREF with 26 items and four domains of health, namely, physical, psycholog- ical, social relationships, and environmental is considered an equally valid and reliable alternative to the assessment of domain profiles used in the WHOQOL-100 (WHOQOL A. R. Usefy Medical Education Research Centre (MERC), Isfahan University of Medical Sciences, Isfahan, Iran Gh. R. Ghassemi (&) Department of Psychiatry, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran e-mail: ghassemi@med.mui.ac.ir; zcswei@gmail.com N. Sarrafzadegan Isfahan Cardiovascular Research Centre, Isfahan University of Medical Sciences, Isfahan, Iran S. Mallik Zenderood Clinic of Social Work, Isfahan, Iran A. M. Baghaei Isfahan Cardiovascular Research Centre, WHO Collaborating Centre, Isfahan University of Medical Sciences, Isfahan, Iran K. Rabiei Cardiac Rehabilitation Department, Isfahan Cardiovascular Research Centre, WHO Collaborating Centre, Isfahan University of Medical Sciences, Isfahan, Iran 123 Community Ment Health J DOI 10.1007/s10597-009-9282-8