Purpose: This paper describes the development of an add-on module for the World Health Organization WHOQOL measures of quality of life for use with adults with physical or intellectual disabilities. The add-on module, known as the WHOQOL-DIS, was derived following standard WHOQOL methodology and is designed to assess people with disabilities.
Results: In the pilot phase of the study, 12 centres from around the world carried out focus groups with people with physical disabilities, people with intellectual disabilities, with their carers, and with relevant professionals in order to identify gaps in the coverage of the WHOQOL-BREF that were relevant for their quality of life. Items generated from the focus groups were then tested in a pilot study with 1,400 respondents from 15 different centres worldwide, with items being tested and reduced using both classical and modern psychometric methods. A field trial study was then carried out with almost 3,800 respondents, again with the use of both classical and modern psychometric methods.
Conclusions: The outcome of the two rounds of data collection and analysis is a 12-item module that can be used in conjunction with the WHOQOL-BREF or the WHOQOL-100 for assessment of quality of life in physically or intellectually disabled people. Further modifications are also proposed for the use of the WHOQOL-BREF with adults with intellectual disabilities, including simplification of wording of some of the items, the use of a three-point response scale, and the inclusion of smiley faces.