Valuing SF-6Dv2 in Australia Using an International Protocol

The SF-6Dv2 is an updated version of the SF-6D, with improved consistency and dimension descriptors, and value sets are required. The aim of this study was to estimate an SF-6Dv2 value set for Australia using an international protocol, while secondary aims were to compare Australian and UK values and to understand heterogeneity.

The study design was based on the SF-6Dv2 valuation protocol, which involved the administration of two different discrete choice experiment (DCE) tasks. The first task presented pairs of SF-6Dv2 health states with duration (Design 1), and the second task presented triplets that appended 'immediate death' to the health state pairs (Design 2). Respondents completed 12 choice sets online (10 from Design 1; 2 from Design 2). Value sets were estimated for Design 1 separately and combining Designs 1 and 2 using a variety of logit model specifications. Value set characteristics were compared descriptively with the UK model.

The sample included 3001 Australians. A range of ordered and consistent models were estimated. The models only including Design 1 data resulted in a relatively wider utility range. The value range was reduced by an interaction added when the health state included a dimension with a severe level. The model matched with the UK value set resulted in a larger utility range and consistent ordering of the most important dimensions.

The model including the Design 1 data and moderating interaction was chosen for the Australian value set. This allows the SF-6Dv2 to be used in health technology assessment decision making in Australia.