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There is a large stated preference literature estimating willingness to pay (WTP) for health risk reductions using the contingent valuation (CVM) approach, and more recently often based on the discrete choice experiment (DCE) approach. Irrespective of method, these studies often fail to show adequate sensitivity to scope, i.e. WTP does not increase as the quantity of the good or the number of goods increases. In this paper we compare the sensitivity to scope with the CVM and DCE approach based on respondents' WTP for mortality and morbidity risk reductions. We analyze scope sensitivity using between-subject tests, which is a novelty in the DCE setting. The results show that we can reject adequate sensitivity to scope in both the CVM and DCE design, and the degrees of bias and welfare estimates are very similar in the two approaches. Thus, using a more stringent scope sensitivity test than the standard approach in the DCE literature indicates that sensitivity to scope is an equal pressing issue in DCE as well as in CVM studies.
