An Australian MAU/QALY Instrument: Rationale and Preliminary Results

The paper presents the preliminary stages in the construction of an Australian Multi-attribute Utility Instrument for obtaining preferences regarding quality of life (QoL) for economic evaluation of health services. The project was undertaken following a review of existing MAU and generic QoL instruments, none of which had been validated for use with an Australian population and most of which did not meet standard psychometric criteria. The definition of `health' adopted by the research team came from the World Health Organization's definition. Following a review of 14 MAU/QoL instruments, a model of health-related QoL was constructed. This involved defining five dimensions: illness, independent living, physical ability, psychological state and social interaction. Focus groups of doctors were used to elicit the content and items appropriate for each dimension. An iterative procedure was followed, during which items were progressively refined until there was an overall consensus about adequate coverage, item content and item language. The item bank was then submitted to a patient sample. The bulk of the paper outlines the procedures which were used to construct a preliminary version of the MAU-instrument, and describes the psychometric properties of this research tool. The paper concludes with a brief review of the further research in progress to verify the structure of the preliminary instrument, to develop appropriate weights and to undertake standard tests of validity and reliability.