Validity and reliability of the Persian version of measurement of the quality of life of people with disabilities

Improving disabled quality of life is considered as one the goals of rehabilitation and maintaining and ameliorating quality of life has become an important aim of medical systems. This study aims at investigating psychometric properties of measurement of the quality of life of people with disabilities، which is developed by World Health Organization (WHO). The questionnaire was translated based on the International Quality of Life Assessment Project (IQOLA). 160 individuals over 18 years old with disability in Tehran (age average=50) performed in this study. Socio-demographic inventory، SF12 inventory، and finally WHOQOL-D were given to participants respectively. Validity، concurrent validity with quality of life questionnaire (short form 12) by using correlation coefficients pearson، face validity، content validity and discriminant validity with spearman correlation coefficients of internal consistency and stability by calculating Cronbach’s alpha and determining the intraclass correlation coefficients (ICC) was assessed. Version 19 SPSS was used to perform statistical tests. Face and content validity of the questionnaire، simplicity، and clarity were approved phrases. Over 90% of scores with a correlation of each question with the scores of related subtest was significant and positive. These results indicate an appropriate discriminative validity of the test items. Estimating Cronbach’s alpha (0. 90) confirms high internal consistency of the inventory with the exception of social communication area (0. 61). The results of evaluating reliability using within subject correlation coefficient estimation show that there is a high correlation coefficient between different subtests of the inventory. ‍ Results indicate reliability and validity of Persian-version of mentioned inventory. Therefore، its utilization in research studies is highly recommended.