Validation of the abbreviated version of the World Health Organization Quality of Life in Mongolia: a population-based cross-sectional study among adults in Ulaanbaatar

There is currently no validated tool to measure the quality of life (QOL) in the Mongolian language. This study aimed to validate the Mongolian version of the World Health Organization Quality of Life - Brief (WHOQOL-BREF) questionnaire for the general population of Mongolia. The subjects were 301 adults aged 18-65 years selected randomly by a computer from 30 centers in 8 districts of Ulaanbaatar, Mongolia, in 2020. Reliability was measured using Cronbach's α and intraclass correlation coefficients. Convergent, discriminant, and construct validities were examined using exploratory and confirmatory factor analyses for a four-domain factor structure. Among the participants, 56.1% were women, 32.9% held a bachelor's degree or higher, 48.8% were employed, and 61.8% were married. The overall Cronbach's α coefficient of the WHOQOL-BREF questionnaire was 0.804. Correlations between the component scores of the WHOQOL-BREF ranged from 0.581-0.822. All items showed higher item-total correlations with their corresponding domains than with other domains, except the mobility item from the physical domain. Discriminative validity was evident in physical and psychological domains. Exploratory and confirmatory factor analyses revealed a four-factorial structure consisting of 24 items that provided an acceptable fit to the data (RMSEA=0.084; CFI=0.860). In conclusion, the Mongolian version of the WHOQOL-BREF demonstrated evidence of good reliability and validity for assessing QOL in the general population of Mongolia. These findings indicate that it allows the comparison of QOL of adults in Mongolia with those in other countries.