Econometric scaling generally rates the utility of composite health states, so a practical issue is the large number of such health states that may need to be judged. Here, a set of assumptions from multiattribute utility theory allows the investigator to estimate utility weights for composite states from the weights of individual components. Multiattribute utility theory identifies a mathematical formula for extrapolating utility estimates to a wide range of states from direct measurement of preferences for a subset of those states (37, p245). The multiattribute functions may be additive or multiplicative, with each requiring different assumptions of the data (37, p246). In practice, raters use the standard gamble to judge the individual elements (e.g., pain, disability) plus a selection of multiattribute combinations and from this, utility weights for all possible permutations can be estimated (50). This approach has been used in the Health Utilities Index.