Eliciting people's preferences for the distribution of health: A procedure for a more precise estimation of distributional weights

In order to incorporate distributional concerns into cost-effectiveness analysis, it would be useful to elicit distributional weights that express people's valuation of marginal health gains at various levels of health. Distributional preferences are commonly elicited either through a person trade off (PTO) or a gain trade off (GTO) technique. An inherent problem of the GTO is that it is based on the valuation of non-marginal health gains. In practice, many contributions using the PTO also focus on non-marginal health gains. This paper demonstrates that the failure to distinguish appropriately between marginal and non-marginal health gains may lead to seriously misleading estimates of distributional weights. Moreover, the paper proposes a methodology for utilising information obtained through non-marginal analysis more efficiently in order to obtain more reliable estimates of distributional weights. The methodology was successfully applied in an empirical study of age weights.