Background: In the field of intellectual disabilities (ID), the quality of life concept has been developing rapidly in Chinese societies including Hong Kong, mainland China and Taiwan. However, there is a lack of locally validated instruments to measure the quality of life of people with ID. The study reported in this paper attempted to validate the Chinese Quality of Life Questionnaire - Intellectual Disabilities adapted from the Quality of Life Questionnaire developed by Schalock & Keith.
Methods: People with mild/moderate ID aged 15 years or above were recruited from special schools, skills centres, community service units and residential units in different regions of Hong Kong. A number of procedures were followed including reliability tests, factor analysis, content validity and construct validity.
Results: A total of 359 participants were recruited for the study. Factor analysis was conducted according to the rotated component matrix method, in which 23 items were extracted from the original 40-item version of the Quality of Life Questionnaire and three domains (renamed satisfaction, competence and daily choice making/interpersonal relations) were observed. The items in each domain were shown to have factor loadings ranging from 0.42 to 0.90. Construct validity tests indicated the positive nature of the relationship between earnings, and that self-determination and social interaction increase with more independent living environments and less segregated work environments achieving higher scores (P<0.000, P<0.01 and P<0.05 respectively). The scale also achieved a good degree of reliability (Cronbach's α=0.79).
Conclusions: Initial validity tests indicated that the Chinese Quality of Life Questionnaire - Intellectual Disabilities may be a useful instrument for measuring the quality of life of Chinese people with ID. Cultural issues are discussed and recommendations for future research and service development are made.
© 2011 The Authors. Journal of Intellectual Disability Research © 2011 Blackwell Publishing Ltd.