Modelling utility weights for the Assessment of Quality of Life (AQoL)-8D

Purpose The objective of this paper is to describe the four stage methodology used to obtain utility scores for the Assessment of Quality of Life (AQoL)-8D, a 35-item 8 Dimension multi-attribute utility instrument, which was created to achieve a high degree of sensitivity to psycho-social health. Methods Data for the analyses were obtained from a representative group of 347members of the Australian public and from 323mental health patients each of whom provided VAS and time trade-off valuations of multiple health states. Data were used initially to create multiplicative scoring algorithms for each of the instrument?s 8 dimensions and for the overall instrument. Each of the algorithms was then subject to a second-stage econometric `correction?. Results Algorithms were successfully created for each of the AQoL-8D?s dimensions, for physical and mental `super-dimensions? and for the overall AQoL-8D instrument. The final AQoL-8D algorithm has good predictive power with respect to the TTO valuations. Conclusions The AQoL-8D is a suitable instrument for researchers conducting cost utility analyses generally but, in particular, for the analysis of services affecting psychosocial health.